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Sample records for therapeutic radionuclides biophysical

  1. Therapeutic radionuclides: Making the right choice

    International Nuclear Information System (INIS)

    Srivastava, S.C.

    1996-01-01

    Recently, there has been a resurgence of interest in nuclear medicine therapeutic procedures. Using unsealed sources for therapy is not a new concept; it has been around since the beginnings of nuclear medicine. Treatment of thyroid disorders with radioiodine is a classic example. The availability of radionuclides with suitable therapeutic properties for specific applications, as well as methods for their selective targeting to diseased tissue have, however, remained the main obstacles for therapy to assume a more widespread role in nuclear medicine. Nonetheless, a number of new techniques that have recently emerged, (e.g., tumor therapy with radiolabeled monoclonal antibodies, treatment of metastatic bone pain, etc.) appear to have provided a substantial impetus to research on production of new therapeutic radionuclides. Although there are a number of new therapeutic approaches requiring specific radionuclides, only selected broad areas will be used as examples in this article

  2. Mass spectrometry for the biophysical characterization of therapeutic monoclonal antibodies.

    Science.gov (United States)

    Zhang, Hao; Cui, Weidong; Gross, Michael L

    2014-01-21

    Monoclonal antibodies (mAbs) are powerful therapeutics, and their characterization has drawn considerable attention and urgency. Unlike small-molecule drugs (150-600 Da) that have rigid structures, mAbs (∼150 kDa) are engineered proteins that undergo complicated folding and can exist in a number of low-energy structures, posing a challenge for traditional methods in structural biology. Mass spectrometry (MS)-based biophysical characterization approaches can provide structural information, bringing high sensitivity, fast turnaround, and small sample consumption. This review outlines various MS-based strategies for protein biophysical characterization and then reviews how these strategies provide structural information of mAbs at the protein level (intact or top-down approaches), peptide, and residue level (bottom-up approaches), affording information on higher order structure, aggregation, and the nature of antibody complexes. Copyright © 2013 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  3. Biophysics

    CERN Document Server

    Glaser, Roland

    1999-01-01

    The message of this book is that biophysics is the science of physical principles underlying the "phenomenon life" on all levels of organization. Rather than teaching "physics for biologists" or "physical methods applied to biology", it regards its subject as a defined discipline with its own network of ideas and approaches. The book starts by explaining molecular structures of biological systems, various kinds of atomic, molecular and ionic interactions, movements, energy transfer, self organization of supramolecular structures and dynamic properties of biological membranes. It then goes on to introduce the biological organism as a non-equilibrium system, before treating thermodynamic concepts of osmotic and electrolyte equilibria as well as currents and potential profiles. It continues with topics of environmental biophysics and such medical aspects as the influence of electromagnetic fields or radiation on living systems and the biophysics of hearing and noice protection. The book concludes with a discussi...

  4. Introduction [Nuclear data for the production of therapeutic radionuclides

    International Nuclear Information System (INIS)

    Qaim, S.M.

    2011-01-01

    Radioactivity plays an important role in medical science in terms of beneficial applications in both diagnosis and therapy. The former entails the introduction of a short lived radionuclide attached to a suitable pharmaceutical into the patient, and measurement of the accumulation and movement of activity from outside. This process is called emission tomography and involves the measurement of either a single low energy γ ray (i.e. single photon computed emission tomography) or coincidences between the two 511 keV photons formed in the annihilation of a positron (i.e. positron emission tomography (PET)). The major governing principle in all diagnostic studies is that the radiation dose to the patient is as low as possible. Two modalities exist in the therapeutic use of radioactivity. The first and most commonly followed procedure involves the use of external beams of electrons, X rays and γ rays from radioactive sources (e.g. 60 Co), high energy γ rays from accelerators, and hadrons (e.g. neutrons, protons and heavy ions). The second modality involves the introduction of certain radionuclides to a given part of the body (e.g. joints, organ and tumour) either mechanically or via a biochemical pathway. Mechanical introduction is called brachytherapy, whereas the biochemical pathway is known as endoradiotherapy. External radiation therapy is outside the scope of the present studies. The concerted and collaborative efforts described here deal specifically with the production and use of radionuclides. An earlier coordinated research project (CRP) of the IAEA was devoted to diagnostic radionuclides. The present effort is related to therapeutic radionuclides.

  5. Mesenchymal stem cells as therapeutic target of biophysical stimulation for the treatment of musculoskeletal disorders.

    Science.gov (United States)

    Viganò, Marco; Sansone, Valerio; d'Agostino, Maria Cristina; Romeo, Pietro; Perucca Orfei, Carlotta; de Girolamo, Laura

    2016-12-16

    Musculoskeletal disorders are regarded as a major cause of worldwide morbidity and disability, and they result in huge costs for national health care systems. Traditional therapies frequently turned out to be poorly effective in treating bone, cartilage, and tendon disorders or joint degeneration. As a consequence, the development of novel biological therapies that can treat more effectively these conditions should be the highest priority in regenerative medicine. Mesenchymal stem cells (MSCs) represent one of the most promising tools in musculoskeletal tissue regenerative medicine, thanks to their proliferation and differentiation potential and their immunomodulatory and trophic ability. Indeed, MSC-based approaches have been proposed for the treatment of almost all orthopedic conditions, starting from different cell sources, alone or in combination with scaffolds and growth factors, and in one-step or two-step procedures. While all these approaches would require cell harvesting and transplantation, the possibility to stimulate the endogenous MSCs to enhance their tissue homeostasis activity represents a less-invasive and cost-effective therapeutic strategy. Nowadays, the role of tissue-specific resident stem cells as possible therapeutic target in degenerative pathologies is underinvestigated. Biophysical stimulations, and in particular extracorporeal shock waves treatment and pulsed electromagnetic fields, are able to induce proliferation and support differentiation of MSCs from different origins and affect their paracrine production of growth factors and cytokines. The present review reports the attempts to exploit the resident stem cell potential in musculoskeletal pathologies, highlighting the role of MSCs as therapeutic target of currently applied biophysical treatments.

  6. Metallic radionuclides: applications in diagnostic and therapeutic nuclear medicine

    International Nuclear Information System (INIS)

    Weiner, R.E.; Thakur, M.L.

    1995-01-01

    Nuclear Medicine is a medical modality that utilizes radioactivity (radiopharmaceutical) to diagnose and treat disease. Radiopharmaceuticals contain a component which directs the radionuclide to the desire physiological target. For diagnostic applications, these nuclides must emit a γ ray that can penetrate the body and can be detected externally while for therapeutic purposes nuclides are preferred that emit β particles and deliver highly localized tissue damage. 67 Ga citrate is employed to detect chronic occult abscesses, Hodgkin's and non-Hodgkin's lymphomas, lung cancer, hepatoma and melanoma and localizes in these tissues utilizing iron-binding proteins. 201 Thallous chloride, a potassium analogue, used to diagnosis coronary artery disease, is incorporated in muscle tissue via the Na + -K + -ATPase. 111 In labeled autologous white blood cells, used for the diagnosis of acute infections and inflammations, takes advantage of the white cell's role in fighting infections. 111 In is incorporated in other radiopharmaceuticals e.g. polyclonal IgG, OncoScint CR/OV, OctreoScan and Myoscint by coupling diethylenetriaminepentaacetic acid, a chelate, covalently to these molecules. OncoScint CR/OV and Myoscint localize by antigen-antibody interactions while OctreoScan is taken up by malignant cells in a receptor based process. Polyclonal IgG may share some localization characteristics with 67 Ga. 89 Sr, a pure β emitter, is used for palliation of bone pain due to metastatic bone lesions. Bone salts [Ca(PO) 4 ] are increased in these lesions and this radionuclide is taken up similarly to Ca 2+ . 186 Re and 153 Sm bound to polydentate phosphonate chelates are used similarly and follow the phosphate pathway in lesion incorporation. (orig.)

  7. Metallic radionuclides: Applications in diagnostic and therapeutic nuclear medicine

    International Nuclear Information System (INIS)

    Werner, R.E.; Thakur, M. L.

    1997-01-01

    Nuclear Medicine is a medical modality that utilizes radioactivity (radiopharmaceutical) to diagnose and treat disease. Radiopharmaceuticals contain a component which directs the radionuclide to the desire physiological target. For diagnostic applications, these nuclides must emit a gamma ray that can penetrate the body and can be detected externally while for therapeutic purposes nuclides are preferred that emit beta particles and deliver highly localized tissue damage. sup 6 sup 7 Ga citrate is employed to detect chronic occult abscesses, Hodgkin's and non-Hodgkin's lymphomas, lung cancer, hepatoma and melanoma and localizes in these tissues utilizing iron-binding proteins. sup 2 sup 0 sup 1 Thallous chloride, a potassium analogue, used to diagnosis coronary artery disease, is incorporated in muscle tissue via the Na sup + -K sup + -ATPase. sup 1 sup 1 sup 1 In labeled autologous white blood cells, used for the diagnosis of acute infections and inflammations, takes advantage of the white cell's role in fighting infections. sup 1 sup 1 sup 1 In is incorporated in other radiopharmaceuticals e.g. polyclonal IgG, OncoScint CR/OV, OctreoScan and Myoscint by coupling diethylenetriaminepentaacetic acid, a chelate, covalently to these molecules. OncoScint CR/OV and Myoscint localize by antigen-antibody interactions while OctreoScan is taken up by malignant cells in a receptor based process. Polyclonal IgG may share some localization characteristics with sup 6 sup 7 Ga. sup 8 sup 9 Sr, a pure beta emitter, is used for palliation of bone pain due to metastatic bone lesions. Bone salts [Ca(PO) sub 4] are increased in these lesions and this radionuclide is taken up similarly to Ca sup 2 sup +. sup 1 sup 8 sup 6 Re and sup 1 sup 5 sup 3 Sm bound to polydentate phosphonate chelates are used similarly and follow the phosphate pathway in lesion incorporation. (author)

  8. Novel diagnostic and therapeutic radionuclides for the development of innovative radiopharmaceuticals

    CERN Multimedia

    We propose the exploration of novel radionuclides with diagnostic or therapeutic properties from ISOLDE. Access to such unique isotopes will enable the fundamental research in radiopharmaceutical science towards superior treatment, e.g. in nuclear oncology. The systematic investigation of the biological response to the different characteristics of the decay radiation will be performed for a better understanding of therapeutic effects. The development of alternative diagnostic tools will be applied for the management and optimization of radionuclide therapy.

  9. Abstracts of the 9. Brazilian Congress of Biophysics, 2. Brazilian Congress of Pharmacology and Experimental Therapeutics and 19. Brazilian Congress of Physiology

    International Nuclear Information System (INIS)

    1984-01-01

    Abstracts about biophysics, pharmacology, experimental therapeutics and physiology are presented. The use of radioisotopes in radioassays involve topics like biophysics and renal physiology; central nervous system; endocrinology; animal and comparative physiology; general physiology, digestion and nutrition; general pharmacology. (M.A.C.) [pt

  10. Optimal beta-ray shielding thicknesses for different therapeutic radionuclides and shielding materials

    International Nuclear Information System (INIS)

    Cho, Yong In; Kim, Ja Mee; Kim, Jung Hoon

    2017-01-01

    To better understand the distribution of deposited energy of beta and gamma rays according to changes in shielding materials and thicknesses when radionuclides are used for therapeutic nuclear medicine, a simulation was conducted. The results showed that due to the physical characteristics of each therapeutic radionuclide, the thicknesses of shielding materials at which beta-ray shielding takes place varied. Additional analysis of the shielding of gamma ray was conducted for radionuclides that emit both beta and gamma rays simultaneously with results showing shielding effects proportional to the atomic number and density of the shielding materials. Also, analysis of bremsstrahlung emission after beta-ray interactions in the simulation revealed that the occurrence of bremsstrahlung was relatively lower than theoretically calculated and varied depending on different radionuclides. (authors)

  11. Report of the consultants' meeting on comparative laboratory evaluation of therapeutic radionuclides and radiopharmaceuticals

    International Nuclear Information System (INIS)

    1999-12-01

    Therapeutic radiopharmaceuticals consist of two components - the radionuclide and the biological carrier. With regard to the radionuclide, an advantage of targeted radiotherapy is that there are a wide variety of radionuclides with different physical half-lives and radiation qualities that can be applied for this purpose. An important task is to select a radionuclide that is compatible with the needs of a particular clinical application. The identification of the ideal targeted radiotherapeutic for each potential clinical application is a difficult task because of the multitude of variables that must be considered, some relating to the radioisotope, and others to the biological carrier. Hence it is recommended that a Co-ordinated Research Programme be established by the Agency to enable participants to acquire and intercompare the methodological expertise to evaluate the relative merit of therapeutic radiopharmaceuticals. These studies will be performed using a model system selected either from those described in this report or a promising agent that has emerged in the time since this meeting. The molecular carrier will be labelled with 131 I, 125 I as well as other therapeutic radionuclides available to the participant (for example, 90 Y, 186 Re, 188 Re, 153 Sm, 166 Ho, 165 Dy). The potential radiopharmaceuticals will then be compared in a progression of studies evaluating biological integrity after labelling, internalisation and residualization of radioactivity in the tumour cell, in vitro cytotoxicity, tissue distribution, normal organ toxicity (determination of the maximum tolerated dose) and finally, therapeutic efficacy

  12. Nuclear data for the production of therapeutic radionuclides. Summary report of third research coordination meeting

    International Nuclear Information System (INIS)

    Sublet, J.-Ch.; Capote Noy, R.

    2006-08-01

    A summary is given of the Third Research Coordination Meeting on Nuclear Data for the Production of Therapeutic Radionuclides. The new library of evaluated cross-section will cover reactor and accelerator production of therapeutic radionuclides to appropriate specific activities and purity, along with the relevant decay data. A few new reactions were added at this meeting. Technical discussions and the resulting work plan to conclude the data evaluation activities are summarized for every reaction path. Timescales and agreed actions to deliver the database and Technical Report are also given. (author)

  13. Nuclear data for production of therapeutic radionuclides. Summary report of second research coordination meeting

    International Nuclear Information System (INIS)

    Sublet, J.-Ch.; Capote Noy, R.

    2004-11-01

    A summary is given of the Second Research Coordination Meeting on Nuclear Data for Production of Therapeutic Radionuclides. The new library of evaluated cross section will cover the reactor and/or accelerator production of therapeutic radionuclides to appropriate specific activities and purity along with the relevant decay data. There are a significant number of radioisotopes in use or being proposed for therapeutic applications. As a consequence of the work undertaken during the course of this CRP, the resulting completeness and accuracy of the nuclear data for the production of these nuclides to appropriate specific activities and purity along with the re-definition of their decay data should be adequate for safe and efficient medical applications. The radioisotopes to be considered in the CRP were divided into two categories: Established Radioisotopes (therapeutic radioisotopes that have established clinical uses) and Emerging Radioisotopes (less-commonly used but potentially interesting radioisotopes for which medical applications have been demonstrated). Experimental data compilations and selection and preliminary evaluations for each of the reactions were extensively discussed during the meeting. The recommendations for both established and emerging radionuclides, and validation/testing of the cross section library are summarized. Technical discussions and the resulting work plan of the Coordinated Research Programme are summarized for every reaction path to be evaluated, along with actions and deadlines. Participants' contributions to the RCM are also attached. (author)

  14. Effect of Some Therapeutic Agents on the Radionuclides Excretion from Internally Contaminated Rats

    International Nuclear Information System (INIS)

    Aziz, M.; Mangood, Sh.A.; Sohsah, M.A.

    2009-01-01

    The present work was oriented to investigate the effectiveness of Prussian blue (PB), vermiculite and diethylenetriaminepentaacetic acid (CaDTPA) as therapeutic agents for the elimination of either 134 Cs or 60 Co from contaminated rats after intake of one of the isotopes. The study was performed by using 48 adult rats divided into 8 identical groups each of six rats having approximately the same body weight. The groups included a reference group, without isotope or therapeutic agent administration, four groups given one of the isotopes and four groups given the isotopes and treated with different therapeutic regimes. The isotope content of the treated and untreated contaminated rats were followed by daily whole body radiometric counting for three weeks. On plotting log % radionuclide retained as a function of time, elapsed between radionuclide administration and radiometric counting, straight lines were obtained. The results indicate that excretion can mostly be represented by two stages; the first is fast followed by a second slow stage. The % radionuclide excreted, the corresponding rate constant and the biological half-life of each stage was estimated. It was found that the application of PB + vermiculite is more efficient, to remove 134 Cs, from contaminated rats, than PB only and CaDTPA is more efficient to remove 60Co. Therefore, it is recommended to use the three therapeutic agents to remove both isotopes when taken simultaneously

  15. Nuclear data for the production of therapeutic radionuclides. Summary report of first research coordination meeting

    International Nuclear Information System (INIS)

    Sublet, J.-Ch.; Paviotti-Corcuera, R.

    2003-06-01

    Presentations, discussions and conclusions from the First Co-ordination Meeting on Nuclear Data for the Production of Therapeutic Radionuclides are summarised in this report. The main purpose of the meeting was to discuss scientific and technical matters related to the subject and to co-ordinate related tasks. Programmes of work were agreed and assigned, and deadlines were set. Participants emphasized the importance of the completeness and accuracy of the resulting nuclear data for the production of these radionuclides to appropriate specific activities and purity along with the relevant decay data. The recommended data from this Coordinated Research Project should meet the requirements for the safe and efficacious application of therapeutic treatments in nuclear medicine. (author)

  16. Radionuclides for therapeutic applications: Biological and medical aspects (present status, development and expectations)

    International Nuclear Information System (INIS)

    Wambersie, A.; Gahbauer, R.A.

    2002-01-01

    Different multidisciplinary therapeutic strategies and technical approaches are used today in cancer therapy. Among the techniques involving ionizing radiation, therapeutic applications of radioactive nuclides deserve a particular interest ; some clinical indications are well established, while several others are now being investigated, and some of them are promising. The efficacy of radionuclides in therapy often depends on technical factors such as specific activity, purity, chemical presentation, availability, etc. These factors are closely related, at least partly, to the production methods. This justifies the organization of the present Consultant's meeting by the IAEA. Brief information on cancer, its socio-economic aspects, and some data concerning cure rate are presented first

  17. Dosimetric studies of anti-CD20 labeled with therapeutic radionuclides at IPEN/CNEN-SP

    Energy Technology Data Exchange (ETDEWEB)

    Barrio, G.; Dias, C.R.B.R.; Osso Junior, J.A., E-mail: gracielabarrio@gmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2012-07-01

    Radioimmunotherapy (RIT) makes use of monoclonal antibodies (MAb) labeled with alpha/beta radionuclides for therapeutical purposes, leading to tumor irradiation and destruction, preserving the normal organs on the radiation excess. The therapeutic activity to be injected in a specific patient is based on information obtained in dosimetric studies. Beta emitting radionuclides such as {sup 131}I, {sup 188}Re, {sup 90}Y, {sup 177}Lu and {sup 166}Ho are useful for the development of therapeutic radiopharmaceuticals. Anti-CD20 (Rituximab) is a chimeric MAb directed against antigen surface CD20 on B-lymphocytes, used in non-Hodgkin lymphoma treatment (NHL). The association with beta radionuclides have shown greater therapeutic efficacy. Currently, two radiopharmaceuticals with Anti-CD20 for radioimmunotherapy have FDA approval for NHL treatment: {sup 131}I-AntiCD20 (Bexar) and {sup 90}Y-AntiCD20 (Zevalin). Techniques for the radiolabeling of {sup 188}Re-antiCD20 have been recently developed by IPEN-CNEN/SP in order to evaluate the clinical use of this radionuclide in particular. The use of {sup 188}Re (T{sub 1/2} 17h) produced by the decay of {sup 188}W (T{sub 1/2} 69d), from an {sup 188}W/{sup 188}Re generator system, has represented an alternative to RIT. Beyond high energy beta emission for therapy, {sup 188}Re also emits gamma rays (155keV) suitable for image. The aim of this new project is to compare the labeling of anti-CD20 with {sup 188}Re with the same MAb labeled with {sup 131}I, {sup 177}Lu, {sup 90}Y and even {sup 99m}Tc. The first step in this project is the review of the published data available concerning the labeling of this MAb with different radionuclides, along with data obtained at IPEN, taking into account labeling procedures, labeling yields, reaction time, level and kind of impurities and biodistribution studies. The pharmacokinetic code will be developed in Visual Studio.NET platform through VB.NET and C{sup ++} for biodistribution and dosimetric

  18. Report of the 2. research coordination meeting on development of generator technologies for therapeutic radionuclides

    International Nuclear Information System (INIS)

    2006-01-01

    The objectives of this CRP are to evaluate various generator and concentration technologies for 188 W- 188 Re, 99 Mo- 99 mTc and 90 Sr- 90 Y generators, to optimize generator fabrication and use, to standardize quality control techniques for the eluted radionuclides and to provide standardized procedures to participating laboratories. The following issues will be addressed during the CRP. - Development of reproducible methodologies for the preparation of 188 W- 188 Re, 99 Mo- 99 mTc and 90 Sr- 90 Y generators. - Development and evaluation of chromatography adsorbents (Zr/Ti composites) having higher binding capacities and demonstration of their utility in the preparation of column generators for 188 Re and 99 mTc. - Comparison and optimization of technologies for post elution concentration of 188 Re and 99 mTc in order to improve the radioactive concentration. - Development of quality control techniques and specifications for generator eluted therapeutic radionuclides

  19. Combined anti-tumor therapeutic effect of targeted gene, hyperthermia, radionuclide brachytherapy in breast carcinoma

    International Nuclear Information System (INIS)

    Chen Daozhen; Tang Qiusha; Xiang Jingying; Xu Fei; Zhang Li; Wang Junfeng

    2011-01-01

    Objective: To investigate the antitumor therapeutic effect of combined therapy of magnetic induction heating by nano-magnetic particles, herpes simplex virus thymidine kinase gene (HSV-tk suicide gene) and internal radiation in mice bearing MCF-7 breast carcinoma. Methods: The transfection reagents, plasmids heat shock protein-HSV-tk (pHSP-HSV-tk), ferroso-ferric oxide nano-magnetic fluid flow and 188 Re-ganciclovir-bovine serum albumin-nanopaticles (GCV-BSA-NP) were prepared. The heating experiments in vivo were carried out using ferroso-ferric oxide nano-magnetic fluid flow. Sixty mice tumor models bearing MCF-7 breast carcinoma were established and randomly divided into six groups. Group A was the control group, B was gene transfection therapy group, C was hyperthermia group, D was gene transfection therapy combined with radionuclide brachytherapy group, E was gene therapy combined with hyperthermia group, and F was gene therapy, hyperthermia combined with radionuclide brachytherapy group. The tumor growth, tumor mass and histopathological changes were evaluated. The expression of HSV-tk in the groups of B, D, E and F was detected by RT-PCR. Poisson distribution and one-way analysis of variance (ANOVA) were used for statistical analysis by SPSS 10.0 software. Results: In the animal heating experiments, the temperature of tumor increased up to 39.6 degree C, 43.2 degree C, and 48.1 degree C quickly with different injected doses (2, 4 and 6 mg respectively) of nano-magnetic particles and maintained for 40 min. The temperature of tumor tissue reduced to 36.8 degree C, 37.5 degree C and 37.8 degree C in 10 min when alternating magnetic field (AMF) stopped. The tumor mass in Groups C ((452.50±30.29) mg), D ((240.98±35.32)mg), E((231.87±27.41) mg) and F ((141.55±23.78) mg) were much lower than that in Group A ((719.12±22.65) mg) (F=800.07, P<0.01), with the most significant treatment effect in Group F.The tumor mass in Group B((684.05±24.02) mg) was higher than

  20. First meeting on the CRP 'standardized high current solid targets for cyclotron production of diagnostic and therapeutic radionuclides'

    International Nuclear Information System (INIS)

    Winkel, P. van den

    2000-01-01

    The Cyclotron Department of the VUB has three groups performing research in the field of target development, production of radionuclides and their application in nuclear medicine. 1. The Physics Group is busy on the optimization of beam parameters, on the determination of cross sections and on neutron spectrometry. 2. The Inorganic Radiochemistry Group performs research on solid target electroplating (Tl, Zn, Cd, Rh ... ), on optimisation of target carrier geometry and cooling and on automated PC-controlled radiochemistry (Tl-201, Ga-67, In-111) and recovery systems and the associated software written in Modula-2 and Visual Basic. 3. The Organic Radiochemistry Group develops new techniques for radiolabelling of organic molecules (fatty acids, neuroleptics, synthetic polypeptides...) useful in diagnostic and therapeutic nuclear medicine. All three groups take part in bulk productions of radionuclides

  1. Report on the 1. research coordination meeting on 'Development of therapeutic radiopharmaceuticals based on {sup 177}Lu for radionuclide therapy'

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    Radionuclide therapy (RNT) employing radiopharmaceuticals labelled with emitting radionuclides is fast emerging as an important part of nuclear medicine. Radionuclide therapy is effectively utilized for bone pain palliation, thus providing significant improvement in quality of life of patients suffering from pain resulting from bone metastasis. Targeting primary diseases by using specific carrier molecules labelled with radionuclides is also widely investigated and efficacious products have been emerging for the treatment of Lymphoma and Neuroendocrine tumours. In order to ensure the wider use of radiopharmaceuticals, it is essential to carefully consider the choice of radionuclides that together with the carrier molecules will give suitable pharmacokinetic properties and therapeutic efficacy. The criteria for the selection of a radionuclide for radiotherapy are suitable decay characteristics and amenable chemistry. However, the practical considerations in selecting a radionuclide for targeted therapy are availability in high radionuclidic purity as well as high specific activity and low production cost and comfortable delivery logistics. {sup 177}Lu is one of the isotopes emerging as a clear choice for therapy. Worldwide, the isotope is under investigation for approximately 30 different clinical applications, including treatment of colon cancer, metastatic bone cancer, non-Hodgkin's lymphoma, and lung cancer. {sup 177}Lu decays with a half-life of 6.71 d by emission of particles with E{sub max} of 497 keV (78.6%), 384 keV (9.1%) and 176 keV (12.2%). It also emits photons of 113 keV (6.4%) and 208 keV (11%), that are ideally suited for imaging the in-vivo localization and dosimetric calculations applying a gamma camera. The physical half-life of {sup 177}Lu is comparable to that of {sup 131}I, the most widely used therapeutic radionuclide. The long halflife of {sup 177}Lu provides logistic advantage for production, QA/QC of the products as well as feasibility to

  2. Report on the 1. research coordination meeting on 'Development of therapeutic radiopharmaceuticals based on 177Lu for radionuclide therapy'

    International Nuclear Information System (INIS)

    2006-01-01

    Radionuclide therapy (RNT) employing radiopharmaceuticals labelled with emitting radionuclides is fast emerging as an important part of nuclear medicine. Radionuclide therapy is effectively utilized for bone pain palliation, thus providing significant improvement in quality of life of patients suffering from pain resulting from bone metastasis. Targeting primary diseases by using specific carrier molecules labelled with radionuclides is also widely investigated and efficacious products have been emerging for the treatment of Lymphoma and Neuroendocrine tumours. In order to ensure the wider use of radiopharmaceuticals, it is essential to carefully consider the choice of radionuclides that together with the carrier molecules will give suitable pharmacokinetic properties and therapeutic efficacy. The criteria for the selection of a radionuclide for radiotherapy are suitable decay characteristics and amenable chemistry. However, the practical considerations in selecting a radionuclide for targeted therapy are availability in high radionuclidic purity as well as high specific activity and low production cost and comfortable delivery logistics. 177 Lu is one of the isotopes emerging as a clear choice for therapy. Worldwide, the isotope is under investigation for approximately 30 different clinical applications, including treatment of colon cancer, metastatic bone cancer, non-Hodgkin's lymphoma, and lung cancer. 177 Lu decays with a half-life of 6.71 d by emission of particles with E max of 497 keV (78.6%), 384 keV (9.1%) and 176 keV (12.2%). It also emits photons of 113 keV (6.4%) and 208 keV (11%), that are ideally suited for imaging the in-vivo localization and dosimetric calculations applying a gamma camera. The physical half-life of 177 Lu is comparable to that of 131 I, the most widely used therapeutic radionuclide. The long halflife of 177 Lu provides logistic advantage for production, QA/QC of the products as well as feasibility to supply the products to places

  3. Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996-1999. Biokinetics and dosimetry of incorporated radionuclides. Final report

    International Nuclear Information System (INIS)

    Roth, P.; Aubineau-Laniece, I.; Bailly-Despiney, I.

    2000-01-01

    The final report 'Biokinetics and Dosimetry of Incorporated Radionuclides' presented here is one part of the 5 individual reports. The work to be carried out within this project is structured into four Work Packages: Workpackage 1 concentrates on ingested radionuclides, considering doses to the GI tract and radionuclide absorption. A major objective is the development of a new dosimetric model of the GI tract, taking account of most recent data on gut transit and dose to sensitive cells. Workpackage 2 seeks to improve and extend biokinetic and dosimetric models for systemic radionuclides. Existing models for adults and children will be extended to other elements and new models will be developed for the embryo and fetus. Workpackage 3 is to improve assessment of localised distribution of dose within tissues at the cellular level for specific examples of Auger emitters and alpha emitting isotopes, in relation to observed effects. The work will include experimental studies of dose/effect relationship and the development of localisation methods. Workpackage 4 concerns the development of computer codes for the new dosimetric models, quality assurance of the models and the calculation of dose coefficients. Formal sensitivity analysis will be used to identify critical areas of model development and to investigate the effects of variability and incertainty in biokinetic parameters. (orig.)

  4. Application of radionuclide imaging in grading and therapeutic evaluation in patients with fallopian tube dysfunction

    International Nuclear Information System (INIS)

    Liu Zhixiang; Zhang Yanhua; Li Guangzhou; Zhang Peisen; Xie Hai; Sun Tao; Ren Chun'e; Zhang Shizhuang; Jiang Aifang

    2012-01-01

    Objective: To observe the conception status of patients with fallopian tube dysfunction after medical treatment and to guide treatment strategy for patients with different degrees of tubal injury by radionuclide imaging. Methods Six hundred and two patients with at least one side of patent fallopian tube underwent modified fallopian tube radionuclide imaging. The patients were graded as: mild, moderate or severe injury, non-functioning or tubal obstruction. The conception status was analyzed after medical treatment, including abdominal hot pack with Chinese medicine, oral intake of Guizhi tuckahoe capsules,and Kangfu anti-inflammatory anal suppository. The constituent ratios of conception in different groups were compared using χ 2 test and the curative and effective rates were calculated. Results: After 1-6 cycles of medical treatment,patients with fallopian tube dysfunction had a curative rate of 29.5% (46/156) and effective rate of 71.8% (112/156). There was a statistically significant difference among the different degrees of oviduct injury (χ 2 =166.4, P<0.05). After medical treatment,the natural pregnancy rate for patients with bilateral mild, moderate and severe injury was 52.6% (102/194), 42.6% (46/108) and 13.8% (16/116), respectively. The rate for patients with one side of normal tubal function was 78.3% (144/184), which was significantly higher than that of patients with bilateral mild, moderate and severe injury (χ 2 =37.86, 52.09 and 121.71, all P<0.05). The natural pregnancy rates of both mild and moderate injury groups were significantly different from the severe injury group (χ 2 =67.29, 42.82, both P<0.05), but there was no difference between the mild and moderate injury groups (χ 2 =3.29, P>0.05). In the severe injury group, 32.8% (38/116) patients were naturally infertile after the medical treatment, while 53.4% (62/116) patients underwent in vitro fertilization (IVF) and 51.6% (32/62) of them succeeded in pregnancy. Conclusions: The natural

  5. Cyclotron produced {sup 67}Ga, a potential radionuclide for diagnostic and therapeutic applications

    Energy Technology Data Exchange (ETDEWEB)

    Khandaker, Mayeen Uddin, E-mail: mu-khandaker@um.edu.my; Kassim, Hasan Abu [Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Haba, Hiromitsu [Nishina Center for Accelerator-Based Science, RIKEN, Wako, Saitama 351-0198 (Japan)

    2015-04-29

    Production cross-sections of the {sup nat}Zn(d,x){sup 67}Ga reactions have been measured from a 24-MeV deuteron energy down to the threshold by using a stacked-foil activation technique combined with HPGe γ-ray spectrometry. An overall good agreement is found with some of the earlier measurements, whereas a partial agreement is obtained with the theoretical data extracted from the TENDL-2013 library. Physical thick target yield for the {sup 67}Ga radionuclide was deduced using the measured cross-sections, and found in agreement with the directly measured yield available in the literature. This study reveals that a low deuteron energy (<11 MeV) cyclotron and an enriched {sup 66}Zn target could be used to obtain {sup 67}Ga in no carrier added form.

  6. Calculation and Evaluation of Fission Yields and Capture Cross Sections Leading to the Production of Therapeutic Radionuclide by Means of Nuclear Reactors

    International Nuclear Information System (INIS)

    Sublet, J.C.

    2009-01-01

    Much progress has been made in nuclear medicine that involves the use of radionuclides for both diagnosis and therapy. Because of this qualitative and quantitative growth, the adoption of a set of established radionuclides for various applications, the methods of nuclide production need to be addressed and consideration given to other, emerging radionuclides that are judged to be developing in importance. The methods involved are characterized by the transmutation of isotopes by neutron-induced reactions and decays. Therefore, newly evaluated cross sections, fission yields and decay characteristics of relevance to the reactor production of those therapeutic radionuclides have been reviewed. Considerations of the decay schemes of all the nuclides involved are also included. (author)

  7. Mathematical biophysics

    CERN Document Server

    Rubin, Andrew

    2014-01-01

    This book presents concise descriptions and analysis of the classical and modern models used in mathematical biophysics. The authors ask the question "what new information can be provided by the models that cannot be obtained directly from experimental data?" Actively developing fields such as regulatory mechanisms in cells and subcellular systems and electron transport and energy transport in membranes are addressed together with more classical topics such as metabolic processes, nerve conduction and heart activity, chemical kinetics, population dynamics, and photosynthesis. The main approach is to describe biological processes using different mathematical approaches necessary to reveal characteristic features and properties of simulated systems. With the emergence of powerful mathematics software packages such as MAPLE, Mathematica, Mathcad, and MatLab, these methodologies are now accessible to a wide audience. Provides succinct but authoritative coverage of a broad array of biophysical topics and models Wr...

  8. The therapeutic threesome, Iodine 131, Lutetium-111 and Rhenium-188 Radionuclide Trifecta

    International Nuclear Information System (INIS)

    Turner, J.H.

    2007-01-01

    Full text: Affordable, available, cost-effective, safe, efficacious therapeutic radiopharmaceuticals are required for clinical application throughout the world. In-house preparation of non-proprietary therapeutic radiopharmaceuticals at tertiary referral hospitals in all countries following appropriate technology transfer and training at key research and development centres can potentially supply this need. Illustrative examples of novel therapeutic radiopharmaceuticals currently under development in physician sponsored phase II clinical trials and candidates for contemplation of translation to developing countries include: (1) I-131 Rituximab radioimmunotherapy of relapsed/refractory and first-line treatment of non- Hodgkin's lymphoma; (2) Lu-177 octreotate radiopeptide therapy of neuroendocrine malignancy with capecitabine tumour radiosensitization; (3) Re-188 lipiodol intrahepatic arterial therapy of hepatocellular carcinoma. In addition to presentation of preliminary clinical results, the logistics and techniques of preparation, quality control and administration of each of these therapeutic radiopharmaceuticals will be described and the calculation of individual patient dosimetry and issues of radiation safety will also be addressed. 1. Iodine-131 rituximab: I-131 rituximab may be prepared in a hospital department of nuclear medicine equipped with a shielded fume cupboard, using commercially available single-use sterile pyrogen-free labelling kits (Go Medical Industries Pty Ltd, Subiaco, Australia) (1). Individualized prospective dosimetry is performed on each patient by quantitative whole body gamma imaging, to determine the therapeutic administered activity, to provide a maximum safe whole body radiation absorbed dose of 0.75 Gy, which equates to less than 2 Gy to red marrow (2). More than 200 patients with relapsed/refractory non-Hodgkin's lymphoma have been treated at Fremantle Hospital without infection or haemorrhagic incident. Myelosuppression is self

  9. Optimization of production and quality control of therapeutic radionuclides and radiopharmaceuticals. Final report of a co-ordinated research project 1994-1998

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-09-01

    The `renaissance` of the therapeutic applications of radiopharmaceuticals during the last few years was in part due to a greater availability of radionuclides with appropriate nuclear decay properties, as well as to the development of carrier molecules with improved characteristics. Although radionuclides such as {sup 32}P, {sup 89}Sr and {sup 131}I, were used from the early days of nuclear medicine in the late 1930s and early 1940s, the inclusion of other particle emitting radionuclides into the nuclear medicine armamentarium was rather late. Only in the early 1980s did the specialized scientific literature start to show the potential for using other beta emitting nuclear reactor produced radionuclides such as {sup 153}Sm, {sup 166} Ho, {sup 165}Dy and {sup 186-188}Re. Bone seeking agents radiolabelled with the above mentioned beta emitting radionuclides demonstrated clear clinical potential in relieving intense bone pain resulting from metastases of the breast, prostate and lung of cancer patients. Therefore, upon the recommendation of a consultants meeting held in Vienna in 1993, the Co-ordinated Research Project (CRP) on Optimization of the Production and quality control of Radiotherapeutic Radionuclides and Radiopharmaceuticals was established in 1994. The CRP aimed at developing and improving existing laboratory protocols for the production of therapeutic radionuclides using existing nuclear research reactors including the corresponding radiolabelling, quality control procedures; and validation in experimental animals. With the participation of ten scientists from IAEA Member States, several laboratory procedures for preparation and quality control were developed, tested and assessed as potential therapeutic radiopharmaceuticals for bone pain palliation. In particular, the CRP optimised the reactor production of {sup 153}Sm and the preparation of the radiopharmaceutical {sup 153}Sm-EDTMP (ethylene diamine tetramethylene phosphonate), as well as radiolabelling

  10. Optimization of production and quality control of therapeutic radionuclides and radiopharmaceuticals. Final report of a co-ordinated research project 1994-1998

    International Nuclear Information System (INIS)

    1999-09-01

    The 'renaissance' of the therapeutic applications of radiopharmaceuticals during the last few years was in part due to a greater availability of radionuclides with appropriate nuclear decay properties, as well as to the development of carrier molecules with improved characteristics. Although radionuclides such as 32 P, 89 Sr and 131 I, were used from the early days of nuclear medicine in the late 1930s and early 1940s, the inclusion of other particle emitting radionuclides into the nuclear medicine armamentarium was rather late. Only in the early 1980s did the specialized scientific literature start to show the potential for using other beta emitting nuclear reactor produced radionuclides such as 153 Sm, 166 Ho, 165 Dy and 186-188 Re. Bone seeking agents radiolabelled with the above mentioned beta emitting radionuclides demonstrated clear clinical potential in relieving intense bone pain resulting from metastases of the breast, prostate and lung of cancer patients. Therefore, upon the recommendation of a consultants meeting held in Vienna in 1993, the Co-ordinated Research Project (CRP) on Optimization of the Production and quality control of Radiotherapeutic Radionuclides and Radiopharmaceuticals was established in 1994. The CRP aimed at developing and improving existing laboratory protocols for the production of therapeutic radionuclides using existing nuclear research reactors including the corresponding radiolabelling, quality control procedures; and validation in experimental animals. With the participation of ten scientists from IAEA Member States, several laboratory procedures for preparation and quality control were developed, tested and assessed as potential therapeutic radiopharmaceuticals for bone pain palliation. In particular, the CRP optimised the reactor production of 153 Sm and the preparation of the radiopharmaceutical 153 Sm-EDTMP (ethylene diamine tetramethylene phosphonate), as well as radiolabelling techniques and quality control methods for

  11. Studies on therapeutic method of liver cancer(hapatocellular carcinome)by Holmium-166 radionuclide

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Tae; Yoo, H. S.; Kim, M. J.; Han, K. H.; Park, C. I. [Yonsei University Medical College, Seoul (Korea, Republic of)

    1997-07-01

    As the study of radioactive nuclide, Holmium-166 in the treatment of liver cancer(hepatocellular carcinoma), this study was performed under the base of animal experimental. Using dog liver, percutaneous injection of Ho-166 MAA or chitosan with premade dose was done under the ultrasound guidance. Continuously the same procedure as previous one was performed in the skin hapatoma, which was developed by the injection of hepatocellular carcinoma cell in the nude mouse, In case of injected normal liver of dog, imaging study including ultrasound, CT and MRI was done in order to evaluate effect of Ho-166 and pathologic reaction. The result showed well defined nectosis of normal liver as well as skin hepatoma. The area of nectosis is dependent on the dose of injected Ho-166. Generally, pathologic reaction is tissue coagulation nectosis, Ho-166 particles, fibrosis and hemorrhage. In the clinical study, 50 patients with hapatoma was selected for this study under the agreement of patient. Under ultrasound guidance percutaneous injection of Ho-166 Maa or chitosan to tumor was performed and follow-up study was extended from 6 to 12 month. The result showed that 64% of patient were completely treated. Overall, the effect of treatment could be obtained in 41 patient (82%) among 50 hepatoma patient. Conclusively Ho-166 is thought to be a compromising agent in the treatment of hepatocellular carcinoma and one of therapeutic modality, if it is established internally and world-wide. In the future, the popular percutaneous ethanol injection method will be replaced to this method. 19 refs., 1 tabs., 14 figs. (author)

  12. Structural biophysics

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Summaries of research projects conducted during 1978 and 1979 are presented. The structural biophysics group explores the high-resolution structure of biological macromolecules and cell organelles. Specific subject areas include: the basic characteristics of photosynthesis in plants; the chemical composition of individual fly ash particles at the site of their damaging action in tissues; direct analysis of frozen-hydrated biological samples by scanning electron microscopy; yeast genetics; the optical activity of DNA aggregates; measurement and characterization of lipoproteins; function of lipoproteins; and the effect of radiation and pollutants on mammalian cells

  13. An Overview of the Production, Quality Control and Feasibility of Using 90Y as a Therapeutic Radionuclide

    International Nuclear Information System (INIS)

    Venkatesh, M.

    2009-01-01

    90 Y is increasingly accepted world wide as a radionuclide for in-vivo therapy owing to attractive decay features (T1/2 2.67 d; Eβ max 2.28 MeV) and viable production feasibility in high specific activities. 90 Y is most often recommended for treatment of large tumour lesions as the hard β rays are effective in delivering therapeutic dose to large volume. However, possibility of high radiation dose to the critical organs such as bone marrow and kidneys is an important concern that is given due weightage while designing therapy using 90 Y. The best route to avail 90 Y for therapy applications is from 90 Sr, though neutron actiation of natural 89 Y(100% abundance) is feasible. The absorption cross section σ is barely 1.38 b, resulting in low specific activity 90 Y which is useful for limited applications. The possibility of obtaining 90Y through a radionuclide generator as the daughter of a long lived parent 90 Sr (T1/2 28.9 y) is a major advantage that enables access to high specific activity 90 Y. Transporting the 90Y activity to a user institution from a centralized production facility is reasonably feasible and this facilitates its wide spread use. Several generator designs have been developed and reported to access 90 Y. Solvent extraction using a chelating molecule in an organic solvent (0.3M HDEHP/n-dodecane), column chromatography using ion exchange resins (cationic as well as anionic; Dowex-50x8; AG 50x16; Aminex-A5) or inorganic exchanger, membrane based separation using chelating ligand impregnated membranes (CMPO in electrochemical separation are some of the methods reported. Limitations such as elution of 90 Y after initial elution of 90 Sr, availability of 90 Y as a chelated complex which then has to be treated to enable labeling the molecule of interest, possibility of obtaining small quantities of 90 Y owing to radiolytic damages to the separation system components, paucity of special automation gadgets for handling the high activities remotely

  14. Radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Summaries of research projects conducted during 1978 and 1979 are presented. The overall thrust of the research is aimed at understanding the effects of radiation on organisms. Specific subject areas include: the effects of heavy-particle beam nuclear interactions in tissue on dosimetry; tracer studies with radioactive fragments of heavy-ion beams; the effects of heavy/ions on human kidney cells and Chinese hamster cells; the response of a rhabdomyosarcoma tumor system in rats to heavy-ion beams; the use of heavy charged particles in radiotherapy of human cancer; heavy-ion radiography; the biological effects of high magnetic fields; central nervous system neurotoxicity; and biophysical studies on cell membranes

  15. Biophysical radiosensitization

    International Nuclear Information System (INIS)

    Vladescu, C.; Apetroae, M.

    1983-01-01

    Experimental studies on normal and tumor-bearing rats revealed that chronic treatment with hydroquinone (5 mg/kg/day) inhibited catalase activity in liver, spleen, blood, and H 18R tumor. 3 H-hydroquinone (1.5 μCi/g body weight) showed tumor specificity, with maximum radioactivity in the tumor at 1 h after administration. The biological half-time of 3 H-hydroquinone in the tumor was 2 h, but there seems to exist a longer component, since 24 h after administration, some 30% of the maximum radioactivity could be detected in the tumor. Hydroquinone treatment produces a specific inhibition of catalase in the tumor and a higher degree of oxygenation at this level. These findings support the assumption that the mechanism of action of hydroquinone as an anticancer agent is achieved mainly via peroxide production. The oxygenation of the hypoxic tumoral tissue is done at non-toxic levels of hydroquinone, through a natural and specific biophysical pathway, recommanding hydroquinone for combined anticancer treatment (radiotherapy and chemotherapy). (orig.)

  16. Report on the 2nd Research Coordination Meeting on The Development of Therapeutic Radiopharmaceuticals Based on 188Re and 90Y for Radionuclide. Working Document

    International Nuclear Information System (INIS)

    2010-01-01

    Radionuclide therapy is practiced for the treatment of malignant disorders of various organs and tissues as well as for treating certain other diseases such as rheumatoid arthritis. Advances in understanding tumor biology as well as developments in peptide chemistry and monoclonal antibody technology are opening new opportunities for the development of therapeutic radiopharmaceuticals, thereby widening the scope of radionuclide therapy. In addition, particulate based radiopharmaceuticals are useful for treating hepatocarcinoma as well as in radiation synovectomy. With the establishment of new products the demand and application of therapeutic nuclear medicine is expected to grow rapidly. While there are a large number of radioisotopes proposed for targeted therapy, practical considerations had been limiting the number of usable isotopes. Generator-produced radionuclides are an attractive option for the large scale on-site availability of therapeutic isotopes. The IAEA’s CRP on the ‘Development of generator technologies for therapeutic radionuclides’ (2004-2007) was successful in developing technologies for the preparation of 188 W/ 188 Re and 90 Sr/ 90 Y generators for eluting 188 Re and 90 Y of high radionuclidic and chemical purity usable for research applications in the development of therapeutic radiopharmaceuticals. The IAEA’s CRP on ‘The development of therapeutic radiopharmaceuticals based on 188 Re and 90 Y for radionuclide therapy’ was formulated to focus on enhancing the capacity of the 90 Sr/ 90 Y generator; to develop and validate quality control methods for the generator eluate; and to develop therapeutic radiopharmaceuticals based on 188 Re and 90 Y. The first RCM of the CRP was held in Polatom, Warsaw, Poland from 30 June to 4 July 2008. The meeting reviewed the work going on in the different participating laboratories, and the facilities, expertise and capabilities of the different participating groups, and formulated the work plan of

  17. Report on the 2{sup nd} Research Coordination Meeting on The Development of Therapeutic Radiopharmaceuticals Based on {sup 188}Re and {sup 90}Y for Radionuclide. Working Document

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Radionuclide therapy is practiced for the treatment of malignant disorders of various organs and tissues as well as for treating certain other diseases such as rheumatoid arthritis. Advances in understanding tumor biology as well as developments in peptide chemistry and monoclonal antibody technology are opening new opportunities for the development of therapeutic radiopharmaceuticals, thereby widening the scope of radionuclide therapy. In addition, particulate based radiopharmaceuticals are useful for treating hepatocarcinoma as well as in radiation synovectomy. With the establishment of new products the demand and application of therapeutic nuclear medicine is expected to grow rapidly. While there are a large number of radioisotopes proposed for targeted therapy, practical considerations had been limiting the number of usable isotopes. Generator-produced radionuclides are an attractive option for the large scale on-site availability of therapeutic isotopes. The IAEA’s CRP on the ‘Development of generator technologies for therapeutic radionuclides’ (2004-2007) was successful in developing technologies for the preparation of {sup 188}W/{sup 188}Re and {sup 90}Sr/{sup 90}Y generators for eluting {sup 188}Re and {sup 90}Y of high radionuclidic and chemical purity usable for research applications in the development of therapeutic radiopharmaceuticals. The IAEA’s CRP on ‘The development of therapeutic radiopharmaceuticals based on {sup 188}Re and {sup 90}Y for radionuclide therapy’ was formulated to focus on enhancing the capacity of the {sup 90}Sr/{sup 90}Y generator; to develop and validate quality control methods for the generator eluate; and to develop therapeutic radiopharmaceuticals based on {sup 188}Re and {sup 90}Y. The first RCM of the CRP was held in Polatom, Warsaw, Poland from 30 June to 4 July 2008. The meeting reviewed the work going on in the different participating laboratories, and the facilities, expertise and capabilities of the different

  18. Radionuclide generators

    International Nuclear Information System (INIS)

    Lambrecht, R.M.

    1983-01-01

    The status of radionuclide generators for chemical research and applications related to the life sciences and biomedical research are reviewed. Emphasis is placed upon convenient, efficient and rapid separation of short-lived daughter radionuclides in a chemical form suitable for use without further chemical manipulation. The focus is on the production of the parent, the radiochemistry associated with processing the parent and daughter, the selection and the characteristic separation methods, and yields. Quality control considerations are briefly noted. The scope of this review includes selected references to applications of radionuclide generators in radiopharmaceutical chemistry, and the life sciences, particularly in diagnostic and therapeutic medicine. The 99 Mo-sup(99m)Tc generator was excluded. 202 references are cited. (orig.)

  19. Improving cancer treatment with cyclotron produced radionuclides

    International Nuclear Information System (INIS)

    Laughlin, J.S.; Larson, S.M.

    1988-01-01

    This new DOE proposal appropriately builds on past developments. The development and application of radionuclides for diagnosis, treatment and research has been a continuing concern for more than the past three decades. A brief description of this development and previous achievements was considered important in order to provide a frame of reference for the evolving program here. Earlier, the use of certain radionuclides, radon progeny and I-131 in particular, and also x-rays, had been developed by the work of such pioneers as Failla, Quimby and Marinelli. In 1952, at the instigation of Dr. C.P. Rhoads, Director of both Memorial Hospital and Sloan-Kettering Institute, the restoration of the Department of Physics and Biophysics was undertaken in response to a perceived need to promote the utilization of radionuclides and of high energy radiations for therapeutic, diagnostic and research purposes. This resulted in several research and developmental projects with close clinical collaboration in areas of radiation treatment; medical studies with radionuclides and labeled compounds; the diagnostic uses of x-rays; and some projects in surgery and other clinical areas. Aspects of some of these projects that have had some relevance for the evolving AEC-DOE projects are outlined briefly. 34 refs

  20. 2. biophysical work meeting

    International Nuclear Information System (INIS)

    1992-11-01

    The report comprises 18 papers held at the 2nd Biophysical Work Meeting, 11 - 13 September 1991 in Schlema, Germany. The history of biophysics in Germany particularly of radiation biophysics and radon research, measurements of the radiation effects of radon and the derivation of limits, radon balneotherapy and consequences of uranium ore mining are dealt with. (orig.) [de

  1. Biophysics conference 1978

    International Nuclear Information System (INIS)

    1978-01-01

    The main subject on the biophysics meeting was the biophysics of membranes with practical subjects from photosynthesis and the transfer processes on membranes. In radiation biophysics, problems of radiation sensitisation, immunological problems after radiation exposure, the oxygen effect and inhibitory processes in RNS synthesis after radiation exposure were discussed with a view to tumour therapy. (AJ) [de

  2. Experimental study and nuclear model calculations on the $^{192}Os (p, n)^{192}$Ir reaction Comparison of reactor and cyclotron production of the therapeutic radionuclide $^{192}$Ir

    CERN Document Server

    Hilgers, K; Sudar, S; 10.1016/j.apradiso.2004.12.010

    2005-01-01

    In a search for an alternative route of production of the important therapeutic radionuclide /sup 192/Ir (T/sub 1/2/=78.83 d), the excitation function of the reaction /sup 192/Os(p, n)/sup 192/Ir was investigated from its threshold up to 20MeV. Thin samples of enriched /sup 192/Os were obtained by electrodeposition on Ni, and the conventional stacked-foil technique was used for cross section measurements. The experimental data were compared with the results of theoretical calculations using the codes EMPIRE-II and ALICE-IPPE. Good agreement was found with EMPIRE-II, but slightly less with the ALICE-IPPE calculations. The theoretical thick target yield of /sup 192/Ir over the energy range E/sub p/=16 to 8MeV amounts to only 0.16MBq/ mu A.h. A comparison of the reactor and cyclotron production methods is given. In terms of yield and radionuclidic purity of /sup 192/Ir the reactor method appears to be superior; the only advantage of the cyclotron method could be the higher specific activity of the product.

  3. Methods in Modern Biophysics

    CERN Document Server

    Nölting, Bengt

    2006-01-01

    Incorporating recent dramatic advances, this textbook presents a fresh and timely introduction to modern biophysical methods. An array of new, faster and higher-power biophysical methods now enables scientists to examine the mysteries of life at a molecular level. This innovative text surveys and explains the ten key biophysical methods, including those related to biophysical nanotechnology, scanning probe microscopy, X-ray crystallography, ion mobility spectrometry, mass spectrometry, proteomics, and protein folding and structure. Incorporating much information previously unavailable in tutorial form, Nölting employs worked examples and 267 illustrations to fully detail the techniques and their underlying mechanisms. Methods in Modern Biophysics is written for advanced undergraduate and graduate students, postdocs, researchers, lecturers and professors in biophysics, biochemistry and related fields. Special features in the 2nd edition: • Illustrates the high-resolution methods for ultrashort-living protei...

  4. Methods in Modern Biophysics

    CERN Document Server

    Nölting, Bengt

    2010-01-01

    Incorporating recent dramatic advances, this textbook presents a fresh and timely introduction to modern biophysical methods. An array of new, faster and higher-power biophysical methods now enables scientists to examine the mysteries of life at a molecular level. This innovative text surveys and explains the ten key biophysical methods, including those related to biophysical nanotechnology, scanning probe microscopy, X-ray crystallography, ion mobility spectrometry, mass spectrometry, proteomics, and protein folding and structure. Incorporating much information previously unavailable in tutorial form, Nölting employs worked examples and about 270 illustrations to fully detail the techniques and their underlying mechanisms. Methods in Modern Biophysics is written for advanced undergraduate and graduate students, postdocs, researchers, lecturers, and professors in biophysics, biochemistry and related fields. Special features in the 3rd edition: Introduces rapid partial protein ladder sequencing - an important...

  5. New horizons in Biophysics

    Science.gov (United States)

    2011-01-01

    This editorial celebrates the re-launch of PMC Biophysics previously published by PhysMath Central, in its new format as BMC Biophysics published by BioMed Central with an expanded scope and Editorial Board. BMC Biophysics will fill its own niche in the BMC series alongside complementary companion journals including BMC Bioinformatics, BMC Medical Physics, BMC Structural Biology and BMC Systems Biology. PMID:21595996

  6. Biophysics An Introduction

    CERN Document Server

    Glaser, Roland

    2012-01-01

    Biophysics is the science of physical principles underlying all processes of life, including the dynamics and kinetics of biological systems. This fully revised 2nd English edition is an introductory text that spans all steps of biological organization, from the molecular, to the organism level, as well as influences of environmental factors. In response to the enormous progress recently made, especially in theoretical and molecular biophysics, the author has updated the text, integrating new results and developments concerning protein folding and dynamics, molecular aspects of membrane assembly and transport, noise-enhanced processes, and photo-biophysics. The advances made in theoretical biology in the last decade call for a fully new conception of the corresponding sections. Thus, the book provides the background needed for fundamental training in biophysics and, in addition, offers a great deal of advanced biophysical knowledge.

  7. Evaluation of 188Re-labeled PEGylated nanoliposome as a radionuclide therapeutic agent in an orthotopic glioma-bearing rat model

    Directory of Open Access Journals (Sweden)

    Huang FYJ

    2015-01-01

    lifespan of glioma-bearing rats treated with 188Re-liposome was prolonged 10.67% compared to the control group.Conclusion: The radiotherapeutic evaluation by dosimetry and survival studies have demonstrated that passive targeting 188Re-liposome via systemic administration can significantly prolong the lifespan of orthotopic glioma-bearing rats while maintaining reasonable systemic radiation safety. Therefore, 188Re-liposome could be a potential therapeutic agent for glioblastoma multiforme treatment. Keywords: 188Re, liposome, radionuclide therapy, bioluminescent imaging, glioma

  8. Advanced Techniques in Biophysics

    CERN Document Server

    Arrondo, José Luis R

    2006-01-01

    Technical advancements are basic elements in our life. In biophysical studies, new applications and improvements in well-established techniques are being implemented every day. This book deals with advancements produced not only from a technical point of view, but also from new approaches that are being taken in the study of biophysical samples, such as nanotechniques or single-cell measurements. This book constitutes a privileged observatory for reviewing novel applications of biophysical techniques that can help the reader enter an area where the technology is progressing quickly and where a comprehensive explanation is not always to be found.

  9. Encyclopedia of biophysics

    CERN Document Server

    2013-01-01

    The Encyclopedia of Biophysics is envisioned both as an easily accessible source of information and as an introductory guide to the scientific literature. It includes entries describing both Techniques and Systems.  In the Techniques entries, each of the wide range of methods which fall under the heading of Biophysics are explained in detail, together with the value and the limitations of the information each provides. Techniques covered range from diffraction (X-ray, electron and neutron) through a wide range of spectroscopic methods (X-ray, optical, EPR, NMR) to imaging (from electron microscopy to live cell imaging and MRI), as well as computational and simulation approaches. In the Systems entries, biophysical approaches to specific biological systems or problems – from protein and nucleic acid structure to membranes, ion channels and receptors – are described. These sections, which place emphasis on the integration of the different techniques, therefore provide an inroad into Biophysics from a biolo...

  10. Biophysical Regulation of Vascular Differentiation and Assembly

    CERN Document Server

    Gerecht, Sharon

    2011-01-01

    The ability to grow stem cells in the laboratory and to guide their maturation to functional cells allows us to study the underlying mechanisms that govern vasculature differentiation and assembly in health and disease. Accumulating evidence suggests that early stages of vascular growth are exquisitely tuned by biophysical cues from the microenvironment, yet the scientific understanding of such cellular environments is still in its infancy. Comprehending these processes sufficiently to manipulate them would pave the way to controlling blood vessel growth in therapeutic applications. This book assembles the works and views of experts from various disciplines to provide a unique perspective on how different aspects of its microenvironment regulate the differentiation and assembly of the vasculature. In particular, it describes recent efforts to exploit modern engineering techniques to study and manipulate various biophysical cues. Biophysical Regulation of Vascular Differentiation and Assembly provides an inter...

  11. Evaluation of pulmonary hypertension and surgical therapeutic efficacy using first-pass radionuclide pulmonary perfusion imaging in patients with pulmonary hypertension of valvular heart disease

    International Nuclear Information System (INIS)

    Wang Xuemei; Shi Rongfang; Fang Wei; Wang Daoyu; Zhou Baogui; Wang Qi; Pan Shiwei

    2004-01-01

    Objective: To evaluate pulmonary hypertension (PH) and surgical therapeutic efficacy using first-pass radionuclide pulmonary perfusion imaging (FPPPI) and pulmonary perfusion imaging (PPI) in patients with PH of valvular heart disease. Methods: One hundred and sixteen patients with valvular disease were included in the study. Swan-Ganz catheterization, echocardiography, FPPPI and PPI were performed on all patients before surgery. The patients were divided into four groups. Results: 1) Correlation coefficients were 0.856, 0.503 and 0.572 (P<0.01) between lung equilibrium time (LET) by FPPPI, superior lung/low lung ratio (S/L) by PPI , systolic pulmonary arterial pressure (SPAP) from echocardiography and SPAP from the catheter manometer. 2)The sensitivity, specificity and accuracy of PAP using FPPPI measuring were 94.7%, 68.3% and 85.3%, respectively. The sensitivity, specificity and accuracy of PAP using PPI measuring were 78.8%, 52.8% and 70.7%, respectively. The sensitivity, specificity and accuracy of PAP using FPPPI plus PPI measuring were 96.4%, 72.7% and 89.7%, respectively. 3)LET by FPPPI before surgery and 5-14 d after surgery were (27.71 ± 10.85) and (20.96 ± 6.25) s, respectively (P<0.001). SPL by PPI were 1.43 ± 0.41 and 1.30 ± 0.35, respectively (P<0.001). 4) Complete improvement rates of LET in the PAP slightly risen group, moderately risen group and weightily risen group were 47.6%, 34.5% and 1/4, respectively; part improvement rates of LET for corresponding groups were 40.5%, 62.1% and 3/4, respectively (P<0.001). Complete improvement rates of SPL were 31.0%, 34.5% and 0/4, respectively; part improvement rates of SPL were 35.7%, 55.2% and 3/4, respectively (P<0.05). Complete improvement rates of LET + SPL were 57.1%, 58.6% and 1/4; part improvement rates of LET+SPL were 38.1%, 41.4% and 3/4, respectively (P<0.01). Conclusions: 1)FPPPI is better than PPI and echocardiography for evaluating PH in valvular heart disease. 2)Combined FPPPI and PPI can

  12. Biophysical aspects of photodynamic therapy.

    Science.gov (United States)

    Juzeniene, Asta; Nielsen, Kristian Pagh; Moan, Johan

    2006-01-01

    Over the last three decades photodynamic therapy (PDT) has been developed to a useful clinical tool, a viable alternative in the treatment of cancer and other diseases. Several disciplines have contributed to this development: chemistry in the development of new photosensitizing agents, biology in the elucidation of cellular processes involved in PDT, pharmacology and physiology in identifying the mechanisms of distribution of photosensitizers in an organism, and, last but not least, physics in the development of better light sources, dosimetric concepts and construction of imaging devices, optical sensors and spectroscopic methods for determining sensitizer concentrations in different tissues. Physics and biophysics have also helped to focus on the role of pH for sensitizer accumulation, dose rate effects, oxygen depletion, temperature, and optical penetration of light of different wavelengths into various types of tissue. These are all important parameters for optimally effective PDT. The present review will give a brief, physically based, overview of PDT and then discuss some of the main biophysical aspects of this therapeutic modality.

  13. Recent progress in Biophysics

    International Nuclear Information System (INIS)

    Bemski, G.

    1980-03-01

    Recent progress in biophysics is reviewed, and three examples of the use of physical techniques and ideas in biological research are given. The first one deals with the oxygen transporting protein-hemoglobin, the second one with photosynthesis, and the third one with image formation, using nuclear magnetic resonance. (Author) [pt

  14. Biophysics of molecular gastronomy.

    Science.gov (United States)

    Brenner, Michael P; Sörensen, Pia M

    2015-03-26

    Chefs and scientists exploring biophysical processes have given rise to molecular gastronomy. In this Commentary, we describe how a scientific understanding of recipes and techniques facilitates the development of new textures and expands the flavor palette. The new dishes that result engage our senses in unexpected ways. PAPERCLIP. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Biophysical Cancer Transformation Pathway

    Czech Academy of Sciences Publication Activity Database

    Pokorný, Jiří

    2009-01-01

    Roč. 28, č. 2 (2009), s. 105-123 ISSN 1536-8378 Institutional research plan: CEZ:AV0Z20670512 Keywords : Biophysics * Cancer * Electromagnetic fields Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.729, year: 2009

  16. Radionuclide trap

    International Nuclear Information System (INIS)

    McGuire, J.C.

    1978-01-01

    The deposition of radionuclides manganese-54, cobalt-58 and cobalt-60 from liquid sodium coolant is controlled by providing surfaces of nickel or high nickel alloys to extract the radionuclides from the liquid sodium, and by providing surfaces of tungsten, molybdenum or tantalum to prevent or retard radionuclide deposition

  17. Biological toxicity of intracellular radionuclide decay. Part of a coordinated programme on radiation biology of Auger emitters and their therapeutic applications

    International Nuclear Information System (INIS)

    Hofer, K.G.

    1980-06-01

    Internal radiotherapy should be performed with short-lived radionuclides which emit high LET radiation and short ranged radiation, and accumulated within cancers. Based on these considerations, several radionuclides (tritium, copper-64, gallium-67, iodine-123, iodine 125, iodine-131 and astatine-211) were chosen and their toxicity was assessed using cell division in mammalian cultured cells as a criterion. It was apparent that the toxic effects obtained with 125 I greatly exceeded those observed in cells treated with any other radionuclides. The possible hypotheses to explain the excessive radiosensitivity of 125 I were discussed in relation to microdosimetry calculation. It was also found that the division delay induced by radionuclide decay is primarily due to damage to the cell nucleus but not to the plasma membrane. The key problem remains the development of agents which can serve as carriers for radionuclide accumulation within tumors. Although several promising approaches (Synkavit, tamoxifen, iododeoxyuridine, antibodies, liposomes) were investigated, only 125 I-labelled Synkavit would be desirable for clinical application

  18. Theoretical Molecular Biophysics

    CERN Document Server

    Scherer, Philipp

    2010-01-01

    "Theoretical Molecular Biophysics" is an advanced study book for students, shortly before or after completing undergraduate studies, in physics, chemistry or biology. It provides the tools for an understanding of elementary processes in biology, such as photosynthesis on a molecular level. A basic knowledge in mechanics, electrostatics, quantum theory and statistical physics is desirable. The reader will be exposed to basic concepts in modern biophysics such as entropic forces, phase separation, potentials of mean force, proton and electron transfer, heterogeneous reactions coherent and incoherent energy transfer as well as molecular motors. Basic concepts such as phase transitions of biopolymers, electrostatics, protonation equilibria, ion transport, radiationless transitions as well as energy- and electron transfer are discussed within the frame of simple models.

  19. Structure and biophysics

    CERN Document Server

    Puglisi, Joseph D

    2007-01-01

    This volume is a collection of articles from the proceedings of the ISSBMR 7th Course: Structure and Biophysics - New Technologies for Current Challenges in Biology and Beyond. This NATO Advanced Institute (ASI) was held in Erice at the Ettore Majorana Foundation and Centre for Scientific Culture on 22 June through 3 July 2005. The ASI brought together a diverse group of experts in the fields of Structural Biology, Biophysics and Physics. Prominent lecturers, from seven different countries, and students from around the world participated in the NATO ASI organized by Professors Joseph Puglisi (Stanford University, USA) and Alexander Arseniev (Moscow, RU). Advances in nuclear magnetic resonance spectroscopy (NMR) and x-ray crystallography have allowed the three-dimensional structures of many biological macromolecules and their complexes, including the ribosome and RNA polymerase to be solved. Fundamental principles of NMR spectroscopy and dynamics, x-ray crystallography, computation and experimental dynamics we...

  20. Biophysics an introduction

    CERN Document Server

    Cotteril, Rodney

    2002-01-01

    Biophysics: An Introduction, is a concise balanced introduction to this subject. Written in an accessible and readable style, the book takes a fresh, modern approach with the author successfully combining key concepts and theory with relevant applications and examples drawn from the field as a whole. Beginning with a brief introduction to the origins of biophysics, the book takes the reader through successive levels of complexity, from atoms to molecules, structures, systems and ultimately to the behaviour of organisms. The book also includes extensive coverage of biopolymers, biomembranes, biological energy, and nervous systems. The text not only explores basic ideas, but also discusses recent developments, such as protein folding, DNA/RNA conformations, molecular motors, optical tweezers and the biological origins of consciousness and intelligence.

  1. Radionuclide toxicity

    International Nuclear Information System (INIS)

    Galle, P.

    1982-01-01

    The aim of this symposium was to review the radionuclide toxicity problems. Five topics were discussed: (1) natural and artificial radionuclides (origin, presence or emission in the environment, human irradiation); (2) environmental behaviour of radionuclides and transfer to man; (3) metabolism and toxicity of radionuclides (radioiodine, strontium, rare gas released from nuclear power plants, ruthenium-activation metals, rare earths, tritium, carbon 14, plutonium, americium, curium and einsteinium, neptunium, californium, uranium) cancerogenous effects of radon 222 and of its danghter products; (4) comparison of the hazards of various types of energy; (5) human epidemiology of radionuclide toxicity (bone cancer induction by radium, lung cancer induction by radon daughter products, liver cancer and leukaemia following the use of Thorotrast, thyroid cancer; other site of cancer induction by radionuclides) [fr

  2. Radionuclide cisternography

    International Nuclear Information System (INIS)

    Song, H.H.

    1980-01-01

    The purpose of this thesis is to show that radionuclide cisternography makes an essential contribution to the investigation of cerebrospinal fluid (CSF) dynamics, especially for the investigation of hydrocephalus. The technical details of radionuclide cisternography are discussed, followed by a description of the normal and abnormal radionuclide cisternograms. The dynamics of CFS by means of radionuclide cisternography were examined in 188 patients in whom some kind of hydrocephalus was suspected. This study included findings of anomalies associated with hydrocephalus in a number of cases, such as nasal liquorrhea, hygromas, leptomeningeal or porencephalic cysts. The investigation substantiates the value of radionuclide cisternography in the diagnosis of disturbances of CSF flow. The retrograde flow of radiopharmaceutical into the ventricular system (ventricular reflux) is an abnormal phenomenon indicating the presence of communicating hydrocephalus. (Auth.)

  3. Biophysics and systems biology.

    Science.gov (United States)

    Noble, Denis

    2010-03-13

    Biophysics at the systems level, as distinct from molecular biophysics, acquired its most famous paradigm in the work of Hodgkin and Huxley, who integrated their equations for the nerve impulse in 1952. Their approach has since been extended to other organs of the body, notably including the heart. The modern field of computational biology has expanded rapidly during the first decade of the twenty-first century and, through its contribution to what is now called systems biology, it is set to revise many of the fundamental principles of biology, including the relations between genotypes and phenotypes. Evolutionary theory, in particular, will require re-assessment. To succeed in this, computational and systems biology will need to develop the theoretical framework required to deal with multilevel interactions. While computational power is necessary, and is forthcoming, it is not sufficient. We will also require mathematical insight, perhaps of a nature we have not yet identified. This article is therefore also a challenge to mathematicians to develop such insights.

  4. Biophysical pathology in cancer transformation

    Czech Academy of Sciences Publication Activity Database

    Pokorný, Jiří; Pokorný, Jan

    S1, Nov (2013), s. 1-9 ISSN 2324-9110 R&D Projects: GA ČR(CZ) GAP102/11/0649 Institutional support: RVO:68378271 ; RVO:67985882 Keywords : cancer biophysics * Warburg effect * reverse Warburg effect * biological electrodynamics * coherent states Subject RIV: BO - Biophysics

  5. Radiation biophysics in space

    International Nuclear Information System (INIS)

    Buecker, H.; Horneck, G.

    1983-01-01

    In a demonstration experiment bacterium sporules have been exposed to the space vacuum and to the solar radiation field at 254 nm, with the following results: 1) a short vacuum exposition of 1.3 h does not affect the vitality of the sporules, 2) the survival rate of humid sporules after UV-irradiation is consistent with terrestrial control samples, 3) after a simultaneous exposition to vacuum and solar UV-radiation the effect on the sporules is enhanced by a factor of ten as compared to the situation without vaccum exposition. Additional studies in biophysical simulation systems revealed, that the enhanced UV sensitivity is caused by the dehydration of the sporules. By this process the structure of the essential macromolecules in cell, such as DNA and proteins, is modified such that new photo-products can be formed. For these products the cells have no effective repair systems. (AJ) [de

  6. Biophysics of DNA

    CERN Document Server

    Vologodskii, Alexander

    2015-01-01

    Surveying the last sixty years of research, this book describes the physical properties of DNA in the context of its biological functioning. It is designed to enable both students and researchers of molecular biology, biochemistry and physics to better understand the biophysics of DNA, addressing key questions and facilitating further research. The chapters integrate theoretical and experimental approaches, emphasising throughout the importance of a quantitative knowledge of physical properties in building and analysing models of DNA functioning. For example, the book shows how the relationship between DNA mechanical properties and the sequence specificity of DNA-protein binding can be analyzed quantitatively by using our current knowledge of the physical and structural properties of DNA. Theoretical models and experimental methods in the field are critically considered to enable the reader to engage effectively with the current scientific literature on the physical properties of DNA.

  7. Biophysics of radiation action

    International Nuclear Information System (INIS)

    Dertinger, H.

    1984-01-01

    Understanding the cellular response to ionizing radiation is not only necessary to meet the requirements of radioprotection, but also for medical application of radiation in cancer treatment. In terms of radiobiology, cancer therapy means the selective inactivation of malignant cells without affecting the normal healthy tissue. However, for several physical and biological reasons, this ideal situation is normally not attained. The elaboration of biophysical parameters that could be used to improve the selective sterilization of tumor cells has become one of the main activities of cellular radiobiology during the last two decades. Progress in this field has been facilitated by the development of tissue culture techniques allowing to grow and analyze cells in a synthetic nutrient medium. This chapter describes the physical and biological factors which determine cellular radiosensitivity and which are important to know for better understanding the cellular radiation action, in particular with reference to cancer treatment

  8. Theoretical molecular biophysics

    CERN Document Server

    Scherer, Philipp O J

    2017-01-01

    This book gives an introduction to molecular biophysics. It starts from material properties at equilibrium related to polymers, dielectrics and membranes. Electronic spectra are developed for the understanding of elementary dynamic processes in photosynthesis including proton transfer and dynamics of molecular motors. Since the molecular structures of functional groups of bio-systems were resolved, it has become feasible to develop a theory based on the quantum theory and statistical physics with emphasis on the specifics of the high complexity of bio-systems. This introduction to molecular aspects of the field focuses on solvable models. Elementary biological processes provide as special challenge the presence of partial disorder in the structure which does not destroy the basic reproducibility of the processes. Apparently the elementary molecular processes are organized in a way to optimize the efficiency. Learning from nature by means exploring the relation between structure and function may even help to b...

  9. Biophysics and cancer

    CERN Document Server

    Nicolini, Claudio

    1986-01-01

    Since the early times of the Greek philosophers Leucippus and Democritus, and later of the Roman philosopher Lucretius, a simple, fundamental idea emerged that brought the life sciences into the realm of the physical sciences. Atoms, after various interactions, were assumed to acquire stable configurations that corresponded either to the living or to the inanimate world. This simple and unitary theory, which has evolved in successive steps to our present time, remarkably maintained its validity despite several centuries of alternative vicissitudes, and is the foundation of modern biophysics. Some of the recent developments of this ancient idea are the discovery of the direct relationship between spatial structures and chemical activity of such molecules as methane and benzene, and the later discovery of the three-dimensional structure of double-helical DNA, and of its relationship with biological activity. The relationship between the structure of various macromolecules and the function of living cells was on...

  10. Radionuclide carrier

    International Nuclear Information System (INIS)

    Hartman, F.A.; Kretschmar, H.C.; Tofe, A.J.

    1978-01-01

    A physiologically acceptable particulate radionuclide carrier is described. It comprises a modified anionic starch derivative with 0.1% to 1.5% by weight of a reducing agent and 1 to 20% by weight of anionic substituents

  11. The Biophysics Microgravity Initiative

    Science.gov (United States)

    Gorti, S.

    2016-01-01

    Biophysical microgravity research on the International Space Station using biological materials has been ongoing for several decades. The well-documented substantive effects of long duration microgravity include the facilitation of the assembly of biological macromolecules into large structures, e.g., formation of large protein crystals under micro-gravity. NASA is invested not only in understanding the possible physical mechanisms of crystal growth, but also promoting two flight investigations to determine the influence of µ-gravity on protein crystal quality. In addition to crystal growth, flight investigations to determine the effects of shear on nucleation and subsequent formation of complex structures (e.g., crystals, fibrils, etc.) are also supported. It is now considered that long duration microgravity research aboard the ISS could also make possible the formation of large complex biological and biomimetic materials. Investigations of various materials undergoing complex structure formation in microgravity will not only strengthen NASA science programs, but may also provide invaluable insight towards the construction of large complex tissues, organs, or biomimetic materials on Earth.

  12. Biophysics of protein evolution and evolutionary protein biophysics

    Science.gov (United States)

    Sikosek, Tobias; Chan, Hue Sun

    2014-01-01

    The study of molecular evolution at the level of protein-coding genes often entails comparing large datasets of sequences to infer their evolutionary relationships. Despite the importance of a protein's structure and conformational dynamics to its function and thus its fitness, common phylogenetic methods embody minimal biophysical knowledge of proteins. To underscore the biophysical constraints on natural selection, we survey effects of protein mutations, highlighting the physical basis for marginal stability of natural globular proteins and how requirement for kinetic stability and avoidance of misfolding and misinteractions might have affected protein evolution. The biophysical underpinnings of these effects have been addressed by models with an explicit coarse-grained spatial representation of the polypeptide chain. Sequence–structure mappings based on such models are powerful conceptual tools that rationalize mutational robustness, evolvability, epistasis, promiscuous function performed by ‘hidden’ conformational states, resolution of adaptive conflicts and conformational switches in the evolution from one protein fold to another. Recently, protein biophysics has been applied to derive more accurate evolutionary accounts of sequence data. Methods have also been developed to exploit sequence-based evolutionary information to predict biophysical behaviours of proteins. The success of these approaches demonstrates a deep synergy between the fields of protein biophysics and protein evolution. PMID:25165599

  13. Radiobiology, biochemistry and radiation biophysics at CYLAB

    International Nuclear Information System (INIS)

    Ftacnikova, S.

    1998-01-01

    The Cyclotron Laboratory (CYLAB) should fill the gap in the field of nuclear medicine, radiotherapy, basic research, metrology of ionizing radiation, education and implications of accelerator technology existing today in Slovak Republic. The main planned activities of this facility are in the fields of nuclear medicine (production of radioisotopes for Positron Emission Tomography - PET and for oncology) and radiotherapy (neutron capture therapy, fast neutron therapy and proton therapy). The radiobiological and biophysical research will be closely connected with medical applications, particularly with radiotherapy. Problems to be addressed include the determination of the values of Relative Biological Effectiveness (RBE) for different types of ionizing radiation involved in the therapy, microdosimetric measurements and calculations, which are indispensable in the calculation of the absorbed dose (lineal and specific energy spectra) at the cellular and macromolecular level. Radiation biophysics and medical physics help in creating therapeutic plans for radiotherapy (NCT and fast neutron therapy). In nuclear medicine, in diagnostic and therapeutical procedures it is necessary to assess the biodistribution of radiopharmaceuticals and to calculate doses in target and critical organs and to determine whole body burden - effective equivalent dose for newly developed radiopharmaceuticals

  14. Radionuclide data

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    Chapter 8 presents tables on selected alpha, beta, gamma and x-ray emitters by increasing energy; information on specific activity for selected radionuclides; naturally occurring radionuclides; the natural decay series; and the artificially produced neptunium series. A table of alpha emitters is listed by increasing atomic number and by energy. The table of β emitters presented is useful in identifying β emitters whose energies and possibly half-lives have been determined by standard laboratory techniques. It is also a handy guide to β-emitting isotopes for applications requiring specific half-lives and/or energies. Gamma rays for radionuclides of importance to radiological assessments and radiation protection are listed by increasing energy. The energies and branching ratios are important for radionuclide determinations with gamma spectrometry detectors. This section also presents a table of x-ray energies which are useful for radiochemical analyses. A number of nuclides emit x-rays as part of their decay scheme. These x-rays may be counted with Ar proportional counters, Ge planar or n-type Ge co-axial detectors, or thin crystal NaI(T1) scintillation counters. In both cases, spectral measurements can be made and both qualitative and quantitative information obtained on the sample. Nuclear decay data (energy and probability by radiation type) for more than one hundred radionuclides that are important to health physicists are presented in a schematic manner

  15. Radionuclides in thyroid cancer

    International Nuclear Information System (INIS)

    Mahadev, V.

    1980-01-01

    The three main areas of application of radionuclides in thyroid disease will be reviewed. Firstly thyroid radionuclide imaging in thyroid swellings, in relationship to lumps in the neck and ectopic thyroid tissue such as retrosternal goitre, and lingual goitre will be described. Future developments in the field including tomographic scanning, using the coded aperture method, and fluorescent scans and ultrasound are reviewed. The second area of application is the assessment and evaluation of thyroid function and the therapy of Grave's Disease and Plummer's Disease using radioiodine. The importance of careful collection of the line of treatment, results of treatment locally and the follow-up of patients after radioiodine therapy will be described. The third area of application is in the diagnosis and therapy of thyroid cancer. Investigation of thyroid swelling, and the diagnosis of functioning metastases are reported. The therapeutic iodine scan as the sole evidence of functioning metastatic involvement is recorded. Histological thyroid cancer appears to be increasingly encountered in clinical practice and the plan of management in relation to choice of cases for therapeutic scanning is discussed with case reports. Lastly the role of whole body scanning in relationship to biochemical markers is compared. In the changing field of nuclear medicine radionuclide applications in thyroid disease have remained pre-eminent and this is an attempt to reassess its role in the light of newer developments and local experience in the Institute of Radiotherapy, Oncology and Nuclear Medicine. (author)

  16. Radionuclide generators

    International Nuclear Information System (INIS)

    Lambrecht, R.M.; Wollongong Univ.; Tomiyoshi, K.; Sekine, T.

    1997-01-01

    The present status and future directions of research and development on radionuclide generator technology are reported. The recent interest to develop double-neutron capture reactions for production of in vivo generators; neutron rich nuclides for radio-immunotherapeutic pharmaceuticals: and advances with ultra-short lived generators is highlighted. Emphasis is focused on: production of the parent radionuclide; the selection and the evaluation of support materials and eluents with respect to the resultant radiochemical yield of the daughter, and the breakthrough of the radionuclide parent: and, the uses of radionuclide generators in radiopharmaceutical chemistry, biomedical and industrial applications. The 62 Zn → 62 Cu, 66 Ni → 66 Cu, 103m Rh → 103 Rh, 188 W → 188 Re and the 225 Ac → 221 Fr → 213 Bi generators are predicted to be emphasized for future development. Coverage of the 99 Mo → 99m Tc generator was excluded, as it the subject of another review. The literature search ended June, 1996. (orig.)

  17. Radionuclide scanning

    International Nuclear Information System (INIS)

    Shapiro, B.

    1986-01-01

    Radionuclide scanning is the production of images of normal and diseased tissues and organs by means of the gamma-ray emissions from radiopharmaceutical agents having specific distributions in the body. The gamma rays are detected at the body surface by a variety of instruments that convert the invisible rays into visible patterns representing the distribution of the radionuclide in the body. The patterns, or images, obtained can be interpreted to provide or to aid diagnoses, to follow the course of disease, and to monitor the management of various illnesses. Scanning is a sensitive technique, but its specificity may be low when interpreted alone. To be used most successfully, radionuclide scanning must be interpreted in conjunction with other techniques, such as bone radiographs with bone scans, chest radiographs with lung scans, and ultrasonic studies with thyroid scans. Interpretation is also enhanced by providing pertinent clinical information because the distribution of radiopharmaceutical agents can be altered by drugs and by various procedures besides physiologic and pathologic conditions. Discussion of the patient with the radionuclide scanning specialist prior to the study and review of the results with that specialist after the study are beneficial

  18. Role of Membrane Biophysics in Alzheimer's - related cell pathways

    Directory of Open Access Journals (Sweden)

    Donghui eZhu

    2015-05-01

    Full Text Available Cellular membrane alterations are commonly observed in many diseases, including Alzheimer’s disease (AD. Membrane biophysical properties, such as membrane molecular order, membrane fluidity, organization of lipid rafts, and adhesion between membrane and cytoskeleton, play an important role in various cellular activities and functions. While membrane biophysics impacts a broad range of cellular pathways, this review addresses the role of membrane biophysics in amyloid-β peptide aggregation, Aβ-induced oxidative pathways, amyloid precursor protein processing, and cerebral endothelial functions in AD. Understanding the mechanism(s underlying the effects of cell membrane properties on cellular processes should shed light on the development of new preventive and therapeutic strategies for this devastating disease.

  19. Measurement of circulating transcripts and gene cluster analysis predicts and defines therapeutic efficacy of peptide receptor radionuclide therapy (PRRT) in neuroendocrine tumors

    International Nuclear Information System (INIS)

    Bodei, L.; Kidd, M.; Modlin, I.M.; Severi, S.; Nicolini, S.; Paganelli, G.; Drozdov, I.; Kwekkeboom, D.J.; Krenning, E.P.; Baum, R.P.

    2016-01-01

    Peptide receptor radionuclide therapy (PRRT) is an effective method for treating neuroendocrine tumors (NETs). It is limited, however, in the prediction of individual tumor response and the precise and early identification of changes in tumor size. Currently, response prediction is based on somatostatin receptor expression and efficacy by morphological imaging and/or chromogranin A (CgA) measurement. The aim of this study was to assess the accuracy of circulating NET transcripts as a measure of PRRT efficacy, and moreover to identify prognostic gene clusters in pretreatment blood that could be interpolated with relevant clinical features in order to define a biological index for the tumor and a predictive quotient for PRRT efficacy. NET patients (n = 54), M: F 37:17, median age 66, bronchial: n = 13, GEP-NET: n = 35, CUP: n = 6 were treated with 177 Lu-based-PRRT (cumulative activity: 6.5-27.8 GBq, median 18.5). At baseline: 47/54 low-grade (G1/G2; bronchial typical/atypical), 31/49 18 FDG positive and 39/54 progressive. Disease status was assessed by RECIST1.1. Transcripts were measured by real-time quantitative reverse transcription PCR (qRT-PCR) and multianalyte algorithmic analysis (NETest); CgA by enzyme-linked immunosorbent assay (ELISA). Gene cluster (GC) derivations: regulatory network, protein:protein interactome analyses. Statistical analyses: chi-square, non-parametric measurements, multiple regression, receiver operating characteristic and Kaplan-Meier survival. The disease control rate was 72 %. Median PFS was not achieved (follow-up: 1-33 months, median: 16). Only grading was associated with response (p < 0.01). At baseline, 94 % of patients were NETest-positive, while CgA was elevated in 59 %. NETest accurately (89 %, χ 2 = 27.4; p = 1.2 x 10 -7 ) correlated with treatment response, while CgA was 24 % accurate. Gene cluster expression (growth-factor signalome and metabolome) had an AUC of 0.74 ± 0.08 (z-statistic = 2.92, p < 0.004) for predicting

  20. Measurement of circulating transcripts and gene cluster analysis predicts and defines therapeutic efficacy of peptide receptor radionuclide therapy (PRRT) in neuroendocrine tumors

    Energy Technology Data Exchange (ETDEWEB)

    Bodei, L. [European Institute of Oncology, Division of Nuclear Medicine, Milan (Italy); LuGenIum Consortium, Milan, Rotterdam, Bad Berka, London, Italy, Netherlands, Germany (Country Unknown); Kidd, M. [Wren Laboratories, Branford, CT (United States); Modlin, I.M. [LuGenIum Consortium, Milan, Rotterdam, Bad Berka, London, Italy, Netherlands, Germany (Country Unknown); Yale School of Medicine, New Haven, CT (United States); Severi, S.; Nicolini, S.; Paganelli, G. [Istituto Scientifico Romagnolo per lo Studio e la Cura dei Tumori (IRST) IRCCS, Nuclear Medicine and Radiometabolic Units, Meldola (Italy); Drozdov, I. [Bering Limited, London (United Kingdom); Kwekkeboom, D.J.; Krenning, E.P. [LuGenIum Consortium, Milan, Rotterdam, Bad Berka, London, Italy, Netherlands, Germany (Country Unknown); Erasmus Medical Center, Nuclear Medicine Department, Rotterdam (Netherlands); Baum, R.P. [LuGenIum Consortium, Milan, Rotterdam, Bad Berka, London, Italy, Netherlands, Germany (Country Unknown); Zentralklinik Bad Berka, Theranostics Center for Molecular Radiotherapy and Imaging, Bad Berka (Germany)

    2016-05-15

    Peptide receptor radionuclide therapy (PRRT) is an effective method for treating neuroendocrine tumors (NETs). It is limited, however, in the prediction of individual tumor response and the precise and early identification of changes in tumor size. Currently, response prediction is based on somatostatin receptor expression and efficacy by morphological imaging and/or chromogranin A (CgA) measurement. The aim of this study was to assess the accuracy of circulating NET transcripts as a measure of PRRT efficacy, and moreover to identify prognostic gene clusters in pretreatment blood that could be interpolated with relevant clinical features in order to define a biological index for the tumor and a predictive quotient for PRRT efficacy. NET patients (n = 54), M: F 37:17, median age 66, bronchial: n = 13, GEP-NET: n = 35, CUP: n = 6 were treated with {sup 177}Lu-based-PRRT (cumulative activity: 6.5-27.8 GBq, median 18.5). At baseline: 47/54 low-grade (G1/G2; bronchial typical/atypical), 31/49 {sup 18}FDG positive and 39/54 progressive. Disease status was assessed by RECIST1.1. Transcripts were measured by real-time quantitative reverse transcription PCR (qRT-PCR) and multianalyte algorithmic analysis (NETest); CgA by enzyme-linked immunosorbent assay (ELISA). Gene cluster (GC) derivations: regulatory network, protein:protein interactome analyses. Statistical analyses: chi-square, non-parametric measurements, multiple regression, receiver operating characteristic and Kaplan-Meier survival. The disease control rate was 72 %. Median PFS was not achieved (follow-up: 1-33 months, median: 16). Only grading was associated with response (p < 0.01). At baseline, 94 % of patients were NETest-positive, while CgA was elevated in 59 %. NETest accurately (89 %, χ{sup 2} = 27.4; p = 1.2 x 10{sup -7}) correlated with treatment response, while CgA was 24 % accurate. Gene cluster expression (growth-factor signalome and metabolome) had an AUC of 0.74 ± 0.08 (z-statistic = 2.92, p < 0

  1. Radiological and physiological studies on the role of some therapeutic agents used for internal decontamination of radionuclides from male albino rats

    International Nuclear Information System (INIS)

    Mangood, S.A.

    2008-01-01

    With the earths increasing nuclear arsenal and the growing use of nuclear energy, the possibility of radiological accidents involving release of radioactive materials, internal contamination may consequently occurs via inhalation, ingestion or absorption of radioisotopes.Therefore, the present work was oriented to deal with four topics related to the internal decontamination of two of the most widely used isotopes, namely 134 Cs and 60 Co from contaminated rats:-In vitro study aimed to select agents that can strongly bind the two metal ions and elucidate the best conditions and the factors affecting this binding. The tested agents were bentonite, vermiculite and Prussian blue (PB). The sorption capacity of PB and vermiculite for both metal ions was high and equivalent to more than 10 11 Bq 137 Cs or 60 Co per gram sorbent. As bentonite has lower capacity to both isotopes, further in vivo experiments were performed with PB and vermiculite.-In vivo studies, via 5 groups of rats, devoted to investigate the kinetics of excretion of 134 Cs and/or 60 Co from contaminated rats. The biological half lives of excretion, excretion stages for both isotopes and the effect of route of entry on the excretion were estimated.-In vivo studies aimed to investigate the effectiveness of PB + vermiculite and CaDTPA as therapeutic agents for accelerating the elimination of 134 Cs and/or 60 Co from contaminated rats. The study was performed via 6 groups of rats given different regimes of therapy. The results showed the high efficiency of PB + vermiculite for accelerating elimination of 134 Cs and orally administrated 60 Co while CaDTPA succeeded in accelerating intraperitoneally administrated 60 Co. The study proved that oral administration of PB + vermiculite and injection with CaDTPA at the same time is very effective in accelerating elimination of both contaminants simultaneously.-The physiological studies aimed to evaluate the hazardous effects of 134 Cs and/or 60 Co incorporation and

  2. Radionuclide examinations

    International Nuclear Information System (INIS)

    Lentle, B.C.

    1989-01-01

    This paper reports on radionuclide examinations of the pancreas. The pancreas, situated retroperitonally high in the epigastrium, was a particularly difficult organ to image noninvasively before ultrasonography and computed tomography (CT) became available. Indeed the organ still remains difficult to examine in some patients, a fact reflected in the variety of methods available to evaluate pancreatic morphology. It is something of a paradox that the pancreas is metabolically active and physiologically important but that its examination by radionuclide methods has virtually ceased to have any role in day-to-day clinical practice. To some extent this is caused by the tendency of the pancreas's commonest gross diseases emdash carcinoma and pancreatitis, for example emdash to result in nonfunction of the entire organ. Disorders of pancreatic endocrine function have generally not required imaging methods for diagnosis, although an understanding of diabetes mellitus and its nosology has been advanced by radioimmunoassay of plasma insulin concentrations

  3. Integrated Molecular and Cellular Biophysics

    CERN Document Server

    Raicu, Valerica

    2008-01-01

    This book integrates concepts and methods from physics, biology, biochemistry and physical chemistry into a standalone, unitary text of biophysics that aims to provide a quantitative description of structures and processes occurring in living matter. The book introduces graduate physics students and physicists interested in biophysics research to 'classical' as well as emerging areas of biophysics. The advanced undergraduate physics students and the life scientists are also invited to join in, by building on their knowledge of basic physics. Essential notions of biochemistry and biology are introduced, as necessary, throughout the book, while the reader's familiarity with basic knowledge of physics is assumed. Topics covered include interactions between biological molecules, physical chemistry of phospholipids association into bilayer membranes, DNA and protein structure and folding, passive and active electrical properties of the cell membrane, classical as well as fractal aspects of reaction kinetics and di...

  4. Radionuclide transfer

    International Nuclear Information System (INIS)

    Gerber, G.B.

    1993-01-01

    The research project described here had the aim to obtain further information on the transfer of nuclides during pregnancy and lactation. The tests were carried out in mini-pigs and rats receiving unchanging doses of radionuclides with the food. The following findings were revealed for the elements examined: Fe, Se, Cs and Zn were characterized by very high transfer levels in the mother, infant and foetus. A substantial uptake by the mother alone was observed for Co, Ag and Mn. The uptake by the foetus and infant here was 1 to 10 times lower. A preferential concentration in certain tissues was seen for Sr and Tc; the thyroid levels of Tc were about equally high in mothers and infants, while Sr showed less accumulation in the maternal bone. The lanthanide group of substances (Ce, Eu and Gd as well as Y and Ru) were only taken up to a very limited extent. The uptake of the examined radionuclides (Fe, Co, Ag, Ce) with the food ingested was found here to be ten times greater in rats as compared to mini-pigs. This showed that great caution must be observed, if the behaviour of radionuclides in man is extrapolated from relevant data obtained in rodents. (orig./MG) [de

  5. The biophysics of neuronal growth

    International Nuclear Information System (INIS)

    Franze, Kristian; Guck, Jochen

    2010-01-01

    For a long time, neuroscience has focused on biochemical, molecular biological and electrophysiological aspects of neuronal physiology and pathology. However, there is a growing body of evidence indicating the importance of physical stimuli for neuronal growth and development. In this review we briefly summarize the historical background of neurobiophysics and give an overview over the current understanding of neuronal growth from a physics perspective. We show how biophysics has so far contributed to a better understanding of neuronal growth and discuss current inconsistencies. Finally, we speculate how biophysics may contribute to the successful treatment of lesions to the central nervous system, which have been considered incurable until very recently.

  6. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1981-01-01

    Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with the design and measurement of physical parameters used in theory or to support biological experiments. The radiation biophysics program tests and uses the theoretical developments for experimental design, and provides information for further theoretical development through experiments on cellular systems

  7. Radiation dosimetry and radiation biophysics

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    Radiation dosimetry and radiation biophysics are two closely integrated programs whose joint purpose is to explore the connections between the primary physical events produced by radiation and their biological consequences in cellular systems. The radiation dosimetry program includes the theoretical description of primary events and their connection with the observable biological effects. This program also is concerned with design and measurement of those physical parameters used in the theory or to support biological experiments. The radiation biophysics program tests and makes use of the theoretical developments for experimental design. Also, this program provides information for further theoretical development through experiments on cellular systems

  8. Biophysical approach to low back pain: a pilot report.

    Science.gov (United States)

    Foletti, Alberto; Pokorný, Jiry

    2015-01-01

    Since biophysical treatment has been reported to be effective in the general management of pain, we decided to assess the specific effect and treatment duration of this therapeutic strategy in low back pain. We were interested in verifying the possibility that a single clinical procedure could reduce pain and improve patients' quality of life within a period of three months. An Electromagnetic Information Transfer Through Aqueous System was employed to record endogenous therapeutic signals from each individual using an electromagnetic recording device (Med Select 729). A highly significant reduction in the Roland Morris low back pain and disability questionnaire score was observed after 3 months following a single biophysical intervention (11.83 ± 6 at baseline versus 2.3 ± 3.25 at 3 months, p < 0.0001). This preliminary report provides further evidence of the theoretical implications and clinical applications of Quantum Electro Dynamic concepts in biology and medicine.

  9. Radionuclide radiology

    International Nuclear Information System (INIS)

    Scarsbrook, A.F.; Graham, R.N.J.; Perriss, R.W.; Bradley, K.M.

    2006-01-01

    This is the fourth in a series of short reviews of internet-based radiological educational resources, and will focus on radionuclide radiology and nuclear medicine. What follows is a list of carefully selected websites to save time in searching them out. Most of the sites cater for trainee or non-specialist radiologists, but may also be of interest to specialists for use in teaching. This article may be particularly useful to radiologists interested in the rapidly expanding field of positron emission tomography computed tomography (PET-CT). Hyperlinks are available in the electronic version of this article and were all active at the time of going to press (February 2006)

  10. Fundamental Concepts in Biophysics Volume 1

    CERN Document Server

    Jue, Thomas

    2009-01-01

    HANDBOOK OF MODERN BIOPHYSICS Series Editor Thomas Jue, PhD Handbook of Modern Biophysics brings current biophysics topics into focus, so that biology, medical, engineering, mathematics, and physical-science students or researchers can learn fundamental concepts and the application of new techniques in addressing biomedical challenges. Chapters explicate the conceptual framework of the physics formalism and illustrate the biomedical applications. With the addition of problem sets, guides to further study, and references, the interested reader can continue to explore independently the ideas presented. Volume I: Fundamental Concepts in Biophysics Editor Thomas Jue, PhD In Fundamental Concepts in Biophysics, prominent professors have established a foundation for the study of biophysics related to the following topics: Mathematical Methods in Biophysics Quantum Mechanics Basic to Biophysical Methods Computational Modeling of Receptor–Ligand Binding and Cellular Signaling Processes Fluorescence Spectroscopy Elec...

  11. Biophysical applications of satellite remote sensing

    CERN Document Server

    Hanes, Jonathan

    2014-01-01

    Including an introduction and historical overview of the field, this comprehensive synthesis of the major biophysical applications of satellite remote sensing includes in-depth discussion of satellite-sourced biophysical metrics such as leaf area index.

  12. Biophysics

    International Nuclear Information System (INIS)

    Danyluk, S.S.

    1975-01-01

    Research is reported on magnetic resonance spectroscopy of biological molecules, development of clinical applications of stable isotopes, circadian cybernetics, and X-ray crystallography of immunoglobulins. Biological processes occur in fluid media, and ultimately our knowledge of their mechanisms requires detailed information for chemical and molecular structural properties in biological fluids. Magnetic resonance spectroscopy has unique advantages over other approaches in this area that are being exploited in studies currently underway in the group. The program continues to develop along three interrelated lines, measurement and analysis of high resolution spectra for biological molecules (especially nucleic acid constituents and drugs), synthesis of selectively labeled nucleic acid fragments essential for complete spectral assignments, and computation of conformational properties from NMR parameters. This coordinated approach enabled the first complete conformation analysis for a dinucleoside monophosphate, ApA, in aqueous solution. It was found that the conformation is actually a time-average of right helical, loop, and extended conformations, the interchange being extremely rapid on an NMR time scale. Spectral analyses were also completed for all possible ribonucleotide dimers, the assignments again relying heavily on synthesis of appropriate deuterated counterparts. Studies of conformational flexibility in nucleic acid fragments showed that changes in hydrogen ion concentration and temperature produce correlated conformational changes specific for each nucleotidyl unit. Studies were also initiated in three new projects dealing with the effect of hapten binding on antibody structure, counter ion influence on nucleic acid free radicals, and membrane differences between normal and sickled erythrocytes

  13. Biophysical models of radiobiological effects

    International Nuclear Information System (INIS)

    Obaturov, G.M.

    1987-01-01

    Radiobiological effect models at different organization levels, developed by the author, are presented. Classification and analysis of concepts and biophysical models at molecular, genetic and cellular levels, developed by Soviet and foreign authors in comparison to inherent models, are conducted from the viewpoint of system approach to radiobiological processes and of modelling principles. Models are compared with each other, limits of their applicability and drawbacks are determined. Evaluation of the model truthfulness is conducted according to a number of criteria, ways of further investigations and experimental examination of some models are proposed

  14. Research Institute for Medical Biophysics

    International Nuclear Information System (INIS)

    Wynchank, S.

    1989-01-01

    The effects of ionising and non-ionising radiation on rodent tumours and normal tissue were studied in terms of cellular repair and the relevant biochemical and biophysical changes following radiation. Rodent tumours investigated in vivo were the CaNT adenocarcinoma and a chemically induced transplantable rhabdomyosarcoma. Radiations used were 100KVp of X-Rays, neutron beams, various magnetic fields, and microwave radiation of 2450MHz. The biochemical parameters measured were, inter alia, levels of adenosine-5'-triphoshate (ATP) and the specific activity of hexokinase (HK). Metabolic changes in ATP levels and the activity of HK were observed in tumour and normal tissues following ionising and non-ionising radiation in normoxia and hypoxia. The observation that the effect of radiation and chemotherapeutic treatment of some tumours may be size dependent can possibly now be explained by the variation of ATP content with tumour size. The enhanced tumour HK specific activity implies increased metabolism, possibly a consequence of cellular requirements to maintain homeostasis during repair processes. Other research projects of the Research Institute for Medical Biophysics involved, inter alia, gastroesophageal scintigraphies to evaluate the results of new forms of therapy. 1 ill

  15. Therapeutic nuclear medicine

    International Nuclear Information System (INIS)

    Baum, Richard P.

    2014-01-01

    Discusses all aspects of radionuclide therapy, including basic principles, newly available treatments, regulatory requirements, and future trends. Provides the knowledge required to administer radionuclide therapy safely and effectively in the individual patient. Explains the role of the therapeutic nuclear physician in effectively coordinating a diverse multidisciplinary team. Written by leading experts. The recent revolution in molecular biology offers exciting new opportunities for targeted radionuclide therapy. The selective irradiation of tumor cells through molecular biological mechanisms is now permitting the radiopharmaceutical control of tumors that are unresectable and unresponsive to either chemotherapy or conventional radiotherapy. In this up-to-date, comprehensive book, world-renowned experts discuss the basic principles of radionuclide therapy, explore in detail the available treatments, explain the regulatory requirements, and examine likely future developments. The full range of clinical applications is considered, including thyroid cancer, hematological malignancies, brain tumors, liver cancer, bone and joint disease, and neuroendocrine tumors. The combination of theoretical background and practical information will provide the reader with all the knowledge required to administer radionuclide therapy safely and effectively in the individual patient. Careful attention is also paid to the important role of the therapeutic nuclear physician in delivering the effective coordination of a diverse multidisciplinary team that is essential to the safe provision of treatment.

  16. Therapeutic nuclear medicine

    Energy Technology Data Exchange (ETDEWEB)

    Baum, Richard P. (ed.) [ENETS Center of Excellence, Bad Berka (Germany). THERANOSTICS Center for Molecular Radiotherapy and Molecular Imaging

    2014-07-01

    Discusses all aspects of radionuclide therapy, including basic principles, newly available treatments, regulatory requirements, and future trends. Provides the knowledge required to administer radionuclide therapy safely and effectively in the individual patient. Explains the role of the therapeutic nuclear physician in effectively coordinating a diverse multidisciplinary team. Written by leading experts. The recent revolution in molecular biology offers exciting new opportunities for targeted radionuclide therapy. The selective irradiation of tumor cells through molecular biological mechanisms is now permitting the radiopharmaceutical control of tumors that are unresectable and unresponsive to either chemotherapy or conventional radiotherapy. In this up-to-date, comprehensive book, world-renowned experts discuss the basic principles of radionuclide therapy, explore in detail the available treatments, explain the regulatory requirements, and examine likely future developments. The full range of clinical applications is considered, including thyroid cancer, hematological malignancies, brain tumors, liver cancer, bone and joint disease, and neuroendocrine tumors. The combination of theoretical background and practical information will provide the reader with all the knowledge required to administer radionuclide therapy safely and effectively in the individual patient. Careful attention is also paid to the important role of the therapeutic nuclear physician in delivering the effective coordination of a diverse multidisciplinary team that is essential to the safe provision of treatment.

  17. Nanoscale biophysics of the cell

    CERN Document Server

    Ashrafuzzaman, Mohammad

    2018-01-01

    Macroscopic cellular structures and functions are generally investigated using biological and biochemical approaches. But these methods are no longer adequate when one needs to penetrate deep into the small-scale structures and understand their functions. The cell is found to hold various physical structures, molecular machines, and processes that require physical and mathematical approaches to understand and indeed manipulate them. Disorders in general cellular compartments, perturbations in single molecular structures, drug distribution therein, and target specific drug-binding, etc. are mostly physical phenomena. This book will show how biophysics has revolutionized our way of addressing the science and technology of nanoscale structures of cells, and also describes the potential for manipulating the events that occur in them.

  18. Quantum Nanobiology and Biophysical Chemistry

    DEFF Research Database (Denmark)

    2013-01-01

    An introduction was provided in the first issue by way of an Editorial to this special two issue volume of Current Physical Chemistry – “Quantum Nanobiology and Biophysical Chemistry” [1]. The Guest Editors would like to thank all the authors and referees who have contributed to this second issue....... Wu et al. use density functional theory to explore the use of Ni/Fe bimetallic nanotechnology in the bioremediation of decabromo-diphenyl esters. Araújo-Chaves et al. explore the binding and reactivity of Mn(III) porphyrins in the membrane mimetic setting of model liposomal systems. Claussen et al....... demonstrate extremely low detection performance of acyl-homoserine lactone in a biologically relevant system using surface enhanced Raman spectroscopy. Sugihara and Bondar evaluate the influence of methyl-groups and the protein environment on retinal geometries in rhodopsin and bacteriorhodopsin, two...

  19. Radionuclides in terrestrial ecosystems

    International Nuclear Information System (INIS)

    Allen, S.E.; Horrill, A.D.; Howard, B.J.; Lowe, V.P.W.; Parkinson, J.A.

    1983-07-01

    The subject is discussed under the headings: concentration and spatial distribution of radionuclides in grazed and ungrazed saltmarshes; incorporation of radionuclides by sheep grazing on an estuarine saltmarsh; inland transfer of radionuclides by birds feeding in the estuaries and saltmarshes at Ravenglass; radionuclides in contrasting types of coastal pastures and taken up by individual plant species found in west Cumbria; procedures developed and used for the measurement of alpha and gamma emitters in environmental materials. (U.K.)

  20. Dosimetry in radionuclide therapy

    International Nuclear Information System (INIS)

    Riccabona, G.

    2001-01-01

    While it is known that therapeutic effects of radionuclides are due to absorbed radiation dose and to radiosensitivity, individual dosimetry in 'Gy' is practiced rarely in clinical Nuclear Medicine but 'doses' are described in 'mCi' or 'MBq', which is only indirectly related to 'Gy' in the target. To estimate 'Gy', the volume of the target, maximum concentration of the radiopharmaceutical in it and residence time should be assessed individually. These parameters can be obtained usually only with difficulty, involving possibly also quantitative SPET or PET, modern imaging techniques (sonography, CT, MRT), substitution of y- or positron emitting radiotracers for β - emitting radiopharmaceuticals as well as whole-body distribution studies. Residence time can be estimated by obtaining data on biological half-life of a comparable tracer and transfer of these data in the physical characteristics of the therapeutic agent. With all these possibilities for gross dosimetry the establishment of a dose-response-relation should be possible. As distribution of the radiopharmaceutical in lesions is frequently inhomogenous and microdosimetric conditions are difficult to assess in vivo as yet, it could be observed since decades that empirically set, sometimes 'fixed' doses (mCi or MBq) can also be successful in many diseases. Detailed dosimetric studies, however, are work- and cost-intensive. Nevertheless, one should be aware at a time when more sophisticated therapeutic possibilities in Nuclear Medicine arise, that we should try to estimate radiation dose (Gy) in our new methods even as differences in individual radiosensitivity cannot be assessed yet and studies to define individual radiosensitivity in lesions should be encouraged. (author)

  1. Historical and Critical Review on Biophysical Economics

    Science.gov (United States)

    Adigüzel, Yekbun

    2016-07-01

    Biophysical economics is initiated with the long history of the relation of economics with ecological basis and biophysical perspectives of the physiocrats. It inherently has social, economic, biological, environmental, natural, physical, and scientific grounds. Biological entities in economy like the resources, consumers, populations, and parts of production systems, etc. could all be dealt by biophysical economics. Considering this wide scope, current work is a “biophysical economics at a glance” rather than a comprehensive review of the full range of topics that may just be adequately covered in a book-length work. However, the sense of its wide range of applications is aimed to be provided to the reader in this work. Here, modern approaches and biophysical growth theory are presented after the long history and an overview of the concepts in biophysical economics. Examples of the recent studies are provided at the end with discussions. This review is also related to the work by Cleveland, “Biophysical Economics: From Physiocracy to Ecological Economics and Industrial Ecology” [C. J. Cleveland, in Advances in Bioeconomics and Sustainability: Essay in Honor of Nicholas Gerogescu-Roegen, eds. J. Gowdy and K. Mayumi (Edward Elgar Publishing, Cheltenham, England, 1999), pp. 125-154.]. Relevant parts include critics and comments on the presented concepts in a parallelized fashion with the Cleveland’s work.

  2. Engineered biomaterial and biophysical stimulation as combinatorial strategies to address prosthetic infection by pathogenic bacteria.

    Science.gov (United States)

    Boda, Sunil Kumar; Basu, Bikramjit

    2017-10-01

    A plethora of antimicrobial strategies are being developed to address prosthetic infection. The currently available methods for implant infection treatment include the use of antibiotics and revision surgery. Among the bacterial strains, Staphylococcus species pose significant challenges particularly, with regard to hospital acquired infections. In order to combat such life threatening infectious diseases, researchers have developed implantable biomaterials incorporating nanoparticles, antimicrobial reinforcements, surface coatings, slippery/non-adhesive and contact killing surfaces. This review discusses a few of the biomaterial and biophysical antimicrobial strategies, which are in the developmental stage and actively being pursued by several research groups. The clinical efficacy of biophysical stimulation methods such as ultrasound, electric and magnetic field treatments against prosthetic infection depends critically on the stimulation protocol and parameters of the treatment modality. A common thread among the three biophysical stimulation methods is the mechanism of bactericidal action, which is centered on biophysical rupture of bacterial membranes, the generation of reactive oxygen species (ROS) and bacterial membrane depolarization evoked by the interference of essential ion-transport. Although the extent of antimicrobial effect, normally achieved through biophysical stimulation protocol is insufficient to warrant therapeutic application, a combination of antibiotic/ROS inducing agents and biophysical stimulation methods can elicit a clinically relevant reduction in viable bacterial numbers. In this review, we present a detailed account of both the biomaterial and biophysical approaches for achieving maximum bacterial inactivation. Summarizing, the biophysical stimulation methods in a combinatorial manner with material based strategies can be a more potent solution to control bacterial infections. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B

  3. Characterization of Tumor-Avid Antibody Fragments Genetically Engineered for Mono-Specific Radionuclide Chelation

    International Nuclear Information System (INIS)

    Quinn, T.P.

    2003-01-01

    The successful clinical application of targeted-radiopharmaceuticals depends on the development of molecules that optimize tumor specific radionuclide deposition and minimize non-specific organ irradiation. To this end, this proposal outlines a research effort to identify and evaluate novel antibodies and antibody fragments that bind breast tumors. The tumor-avid antibodies will be investigated for as imaging and therapeutic agents and to gain a better understanding of the pharmacokinetics and metabolism of radiolabeled tumor-avid antibody fragments through the use of site-specifically labeled molecules. Antibodies or antibody fragments, that bind breast carcinoma carbohydrate antigens, will be obtained from hybridoma or bacteriophage library screening. More specifically, antibody fragments that bind the carcinoma-associated Thomsen-Friedenreich (T) antigen will be radiolabeled with 99m Tc and 188 Re at a natural amino acid chelation site and will be investigated in vivo for their abilities to target human breast tumors. In addition, site-specific radiolabeled antibody fragments will be biosynthesized using misacylated suppressor tRNAs. Homogeneously radiolabeled populations of antibody fragments will be used to investigate the effects of radionuclide location and chelation chemistries on their biodistribution and metabolism. It is hypothesized that site-specifically radiolabeled antibody fragments will possess enhanced tumor imaging and therapeutic properties due to optimal label location and conjugation chemistries. New insights into the factors that govern antibody metabolism in vivo are also expected from this work. Results from these studies should enhance our ability to design and synthesize radiolabeled antibody fragments that have improved pharmacokinetic properties. The studies in this proposal involve basic research into the development of antibody-based radiopharmaceuticals, with the ultimate goal of application in humans. This type of basic nuclear

  4. An introduction to environmental biophysics

    CERN Document Server

    Campbell, Gaylon S

    1977-01-01

    The study of environmental biophysics probably began earlier in man's history than that of any other science. The study of organism-environment interaction provided a key to survival and progress. Systematic study of the science and recording of experimental results goes back many hundreds of years. Ben­ jamin Franklin, the early American statesman, inventor, printer, and scientist studied conduction, evaporation, and radiation. One of his observations is as follows: My desk on which I now write, and the lock of my desk, are both exposed to the same temperature of the air, and have therefore the same degree of heat or cold; yet if I lay my hand successively on the wood and on the metal, the latter feels much the coldest, not that it is really so, but being a better conductor, it more readily than the wood takes away and draws into itself the fire that was in my skin. 1 Franklin probably was not the first to discover this principle, and certainly was not the last. Modem researchers rediscover this principle f...

  5. Mechanoresponsive stem cells to target cancer metastases through biophysical cues.

    Science.gov (United States)

    Liu, Linan; Zhang, Shirley X; Liao, Wenbin; Farhoodi, Henry P; Wong, Chi W; Chen, Claire C; Ségaliny, Aude I; Chacko, Jenu V; Nguyen, Lily P; Lu, Mengrou; Polovin, George; Pone, Egest J; Downing, Timothy L; Lawson, Devon A; Digman, Michelle A; Zhao, Weian

    2017-07-26

    Despite decades of effort, little progress has been made to improve the treatment of cancer metastases. To leverage the central role of the mechanoenvironment in cancer metastasis, we present a mechanoresponsive cell system (MRCS) to selectively identify and treat cancer metastases by targeting the specific biophysical cues in the tumor niche in vivo. Our MRCS uses mechanosensitive promoter-driven mesenchymal stem cell (MSC)-based vectors, which selectively home to and target cancer metastases in response to specific mechanical cues to deliver therapeutics to effectively kill cancer cells, as demonstrated in a metastatic breast cancer mouse model. Our data suggest a strong correlation between collagen cross-linking and increased tissue stiffness at the metastatic sites, where our MRCS is specifically activated by the specific cancer-associated mechano-cues. MRCS has markedly reduced deleterious effects compared to MSCs constitutively expressing therapeutics. MRCS indicates that biophysical cues, specifically matrix stiffness, are appealing targets for cancer treatment due to their long persistence in the body (measured in years), making them refractory to the development of resistance to treatment. Our MRCS can serve as a platform for future diagnostics and therapies targeting aberrant tissue stiffness in conditions such as cancer and fibrotic diseases, and it should help to elucidate mechanobiology and reveal what cells "feel" in the microenvironment in vivo. Copyright © 2017 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  6. Speciation analysis of radionuclides

    International Nuclear Information System (INIS)

    Salbu, B.

    2010-01-01

    Full text: Naturally occurring and artificially produced radionuclides in the environment can be present in different physico-chemical forms (i. e. radionuclide species) varying in size (nominal molecular mass), charge properties and valence, oxidation state, structure and morphology, density, complexing ability etc. Low molecular mass (LMM) species are believed to be mobile and potentially bioavailable, while high molecular mass (HMM) species such as colloids, polymers, pseudocolloids and particles are considered inert. Due to time dependent transformation processes such as mobilization of radionuclide species from solid phases or interactions of mobile and reactive radionuclide species with components in soils and sediments, however, the original distribution of radionuclides deposited in ecosystems will change over time and influence the ecosystem behaviour. To assess the environmental impact from radionuclide contamination, information on radionuclide species deposited, interactions within affected ecosystems and the time-dependent distribution of radionuclide species influencing mobility and biological uptake is essential. The development of speciation techniques to characterize radionuclide species in waters, soils and sediments should therefore be essential for improving the prediction power of impact and risk assessment models. The present paper reviews fractionation techniques which should be utilised for radionuclide speciation purposes. (author)

  7. Applications of synchrotron radiation in Biophysics

    International Nuclear Information System (INIS)

    Bemski, G.

    1983-01-01

    A short introduction to the generation of the synchrotron radiation is made. Following, the applications of such a radiation in biophysics with emphasis to the study of the hemoglobin molecule are presented. (L.C.) [pt

  8. Correlations of CTLA-4 exon-1 49 A/G and promoter region 318C/T polymorphisms with the therapeutic efficacy of 131 I radionuclide in graves' disease in Chinese Han population.

    Science.gov (United States)

    Han, Xin-Rui; Wen, Xin; Wang, Shan; Fan, Shao-Hua; Zhuang, Juan; Wang, Yong-Jian; Zhang, Zi-Feng; Li, Meng-Qiu; Hu, Bin; Shan, Qun; Sun, Chun-Hui; Bao, Ya-Xing; Wu, Dong-Mei; Lu, Jun; Zheng, Yuan-Lin

    2017-08-04

    Graves' disease is an autoimmune process in which the thyroid gland is triggered by autoantibodies, resulting in hyperthyroidism. The purpose of the present study is to elucidate whether exon-1 49 A/G and promoter region 318C/T polymorphisms in the CTLA-4 gene. This study consisted of 653 eligible patients with Graves' disease. After receiving 131I radionuclide therapy, these patients were classified into the remission and non-remission groups. A logistic regression-based model was used to analyze independent factors affecting the patient response to 131I radionuclide therapy. The results showed that CTLA-4 49 A/G was closely related to the efficacy of 131 I treatment for Graves' disease (AG + GG vs. AA: OR = 6.543, 95%CI = 2.611 ∼ 16.40, P Graves' disease. Logistic regression analysis indicated that thyroid weight (OR = 0.963, 95%CI = 0.944 ∼ 0.982, P Graves' disease. These data indicated that CTLA-4 exon-1 49 A/G polymorphism may be associated with patient response to radionuclide 131 I therapy in Graves' disease. © 2017 Wiley Periodicals, Inc.

  9. Radionuclide therapy practice and facilities in Europe

    International Nuclear Information System (INIS)

    Hoefnagel, C.A.; Clarke, S.E.M.; Fischer, M.; Chatal, J.F.; Lewington, V.J.; Nilsson, S.; Troncone, L.; Vieira, M.R.

    1999-01-01

    Using a questionnaire the EANM Task Group Radionuclide Therapy in 1993 collected data on the current practice of radionuclide therapy in European countries. Subsequently, at the request of the EANM Executive Committee, the EANM Radionuclide Therapy Committee has made an inventory of the distribution of facilities for radionuclide therapy and undertaken an assessment of the total number of patients treated throughout Europe and of the types of treatment provides, with the aim of supporting the development of policy to adjust the available capacity to the needs by the year 2000. For this purpose, a second, more detailed questionnaire was sent out the members and national advisors of the Committee (see below), who gathered the data for each country that was a member of the EANM at the time. It is concluded that a wide bariation in therapy practice exists across Europe, particularly in the utilisation of radionuclide therapy, the requirement and availability of proper isolation facilities and the background training of those undertaking therapy. More uniform guidelines and legislation are required, although changes in legislation may have a significant impact in some countries. Although there is wide variation in the therapies used in each country, one the whole it appears that there is an underutilisation of nuclear medicine as a therapeutic modality. A rapidly increasing role may be expected, in particular for oncological indications requiring high-dose radionuclide treatment. Therefore there is an urgent need for a greater number of isolation beds in dedicated centers throughout Europe

  10. Quantitative radionuclide angiocardiography

    International Nuclear Information System (INIS)

    Scholz, P.M.; Rerych, S.K.; Moran, J.F.; Newman, G.E.; Douglas, J.M.; Sabiston, D.C. Jr.; Jones, R.H.

    1980-01-01

    This study introduces a new method for calculating actual left ventricular volumes and cardiac output from data recorded during a single transit of a radionuclide bolus through the heart, and describes in detail current radionuclide angiocardiography methodology. A group of 64 healthy adults with a wide age range were studied to define the normal range of hemodynamic parameters determined by the technique. Radionuclide angiocardiograms were performed in patients undergoing cardiac catherization to validate the measurements. In 33 patients studied by both techniques on the same day, a close correlation was documented for measurement of ejection fraction and end-diastolic volume. To validate the method of volumetric cardiac output calcuation, 33 simultaneous radionuclide and indocyanine green dye determinations of cardiac output were performed in 18 normal young adults. These independent comparisons of radionuclide measurements with two separate methods document that initial transit radionuclide angiocardiography accurately assesses left ventricular function

  11. Preparation of Radiopharmaceuticals Labeled with Metal Radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Welch, M.J.

    2012-02-16

    oxygen retention of the tissue and the significantly greater retention amounting in hypoxic tissue. This hypothesis was confirmed in a series of animal studies. Cu-64 can be used both as an imaging radionuclide and a therapeutic radionuclide. The therapeutic efficacy of Cu-64 ATSM was proven in hamsters bearing the CW39 human colorectal tumors. The administration of Cu-64 ATSM significantly increased the survival time of tumor-bearing animals with no acute toxicity. This copper agent therefore shows promise for radiotherapy. The flow tracer Cu-64 PTSM also demonstrates therapeutic potential by inhibiting cancer cells implanted in animal models. Again, this inhibition occurred at doses which showed no sign of toxicity to the animals. Cu-ATSM was translated to humans, under other support a series of tumors were investigated; these included head and neck cancer, non-small cell lung cancer, cervical cancer and renal cancer. Another radionuclide that was investigated was titanium 45. This radionuclide was successfully produced by radiation of a scandium foil with 15 MeV protons. The titanium 45 was processed and separated from residual scandium by high exchange chomotrophy. Titanium titanocene has been utilized as a therapeutic agent; this compound was prepared and studied in vitro and in vivo. Another project was the preparation of cyclodextrin dimers as a new pre-targeting approach for tumor uptake. Beta-cyclodextradin and two other dimers were synthesized. These dimers were studied for the in vivo application. Work continued on the application of the radionuclide already discussed. Technetium 94m, a positron emitting radionuclide of the widely used 99m Tc nuclide was also prepared. This allows the quantification of the uptake of technetium radiopharmaceuticals. In collaboration with Professor David Piwnica-Worms, technetium 94m, sestamibi was studied in animal models and in a limited number of human subjects.

  12. Marine biogeochemistry of radionuclides

    International Nuclear Information System (INIS)

    Fowler, S.W.

    1997-01-01

    Radionuclides entering the ocean from runoff, fallout, or deliberate release rapidly become involved in marine biogeochemical cycles. Sources, sinks and transport of radionuclides and analogue elements are discussed with emphasis placed on how these elements interact with marine organisms. Water, food and sediments are the source terms from which marine biota acquire radionuclides. Uptake from water occurs by surface adsorption, absorption across body surfaces, or a combination of both. Radionuclides ingested with food are either assimilated into tissue or excreted. The relative importance of the food and water pathway in uptake varies with the radionuclide and the conditions under which exposure occurs. Evidence suggests that, compared to the water and food pathways, bioavailability of sediment-bound radionuclides is low. Bioaccumulation processes are controlled by many environmental and intrinsic factors including exposure time, physical-chemical form of the radionuclide, salinity, temperature, competitive effects with other elements, organism size, physiology, life cycle and feeding habits. Once accumulated, radionuclides are transported actively by vertical and horizontal movements of organisms and passively by release of biogenic products, e.g., soluble excreta, feces, molts and eggs. Through feeding activities, particles containing radionuclides are ''packaged'' into larger aggregates which are redistributed upon release. Most radionuclides are not irreversibly bound to such particles but are remineralized as they sink and/or decompose. In the pelagic zones, sinking aggregates can further scavenge particle-reactive elements thus removing them from the surface layers and transporting them to depth. Evidence from both radiotracer experiments and in situ sediment trap studies is presented which illustrates the importance of biological scavenging in controlling the distribution of radionuclides in the water column. (author)

  13. Biophysical characteristics reveal neural stem cell differentiation potential.

    Directory of Open Access Journals (Sweden)

    Fatima H Labeed

    Full Text Available Distinguishing human neural stem/progenitor cell (huNSPC populations that will predominantly generate neurons from those that produce glia is currently hampered by a lack of sufficient cell type-specific surface markers predictive of fate potential. This limits investigation of lineage-biased progenitors and their potential use as therapeutic agents. A live-cell biophysical and label-free measure of fate potential would solve this problem by obviating the need for specific cell surface markers.We used dielectrophoresis (DEP to analyze the biophysical, specifically electrophysiological, properties of cortical human and mouse NSPCs that vary in differentiation potential. Our data demonstrate that the electrophysiological property membrane capacitance inversely correlates with the neurogenic potential of NSPCs. Furthermore, as huNSPCs are continually passaged they decrease neuron generation and increase membrane capacitance, confirming that this parameter dynamically predicts and negatively correlates with neurogenic potential. In contrast, differences in membrane conductance between NSPCs do not consistently correlate with the ability of the cells to generate neurons. DEP crossover frequency, which is a quantitative measure of cell behavior in DEP, directly correlates with neuron generation of NSPCs, indicating a potential mechanism to separate stem cells biased to particular differentiated cell fates.We show here that whole cell membrane capacitance, but not membrane conductance, reflects and predicts the neurogenic potential of human and mouse NSPCs. Stem cell biophysical characteristics therefore provide a completely novel and quantitative measure of stem cell fate potential and a label-free means to identify neuron- or glial-biased progenitors.

  14. Radionuclides in terrestrial ecosystems

    International Nuclear Information System (INIS)

    Bocock, K.L.

    1981-01-01

    This report summarizes information on the distribution and movement of radionuclides in semi-natural terrestrial ecosystems in north-west England with particular emphasis on inputs to, and outputs from ecosystems; on plant and soil aspects; and on radionuclides in fallout and in discharges by the nuclear industry. (author)

  15. Nuclear data for production of the therapeutic radionuclides {sup 32}P, {sup 64}Cu, {sup 67}Cu, {sup 89}Sr, {sup 9}Y and {sup 153}Sm via the (n,p) reaction: Evaluation of excitation function and its validation via integral cross-section measurement using a 14 MeV d(Be) neutron source

    Energy Technology Data Exchange (ETDEWEB)

    Al-Abyad, M. [Institut fuer Nuklearchemie, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany); Cyclotron Facility, Nuclear Research Center, Atomic Energy Authority, Cairo 13759 (Egypt); Spahn, I. [Institut fuer Nuklearchemie, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany); Institute of Experimental Physics, University of Debrecen, H-4010 Debrecen (Hungary); Sudar, S. [Institut fuer Nuklearchemie, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany); Institute of Experimental Physics, University of Debrecen, H-4010 Debrecen (Hungary); Morsy, M. [Cyclotron Facility, Nuclear Research Center, Atomic Energy Authority, Cairo 13759 (Egypt); Comsan, M.N.H. [Cyclotron Facility, Nuclear Research Center, Atomic Energy Authority, Cairo 13759 (Egypt); Csikai, J. [Institute of Experimental Physics, University of Debrecen, H-4010 Debrecen (Hungary); Qaim, S.M. [Institut fuer Nuklearchemie, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany)]. E-mail: s.m.qaim@fz-juelich.de; Coenen, H.H. [Institut fuer Nuklearchemie, Forschungszentrum Juelich GmbH, D-52425 Juelich (Germany)

    2006-06-15

    Nuclear data for production of the therapeutic radionuclides {sup 32}P, {sup 64}Cu, {sup 67}Cu, {sup 89}Sr, {sup 9}Y and {sup 153}Sm via (n,p) reactions on the target nuclei {sup 32}S, {sup 64}Zn, {sup 67}Zn, {sup 89}Y, {sup 9}Zr and {sup 153}Eu, respectively, are discussed. The available information on each excitation function was analysed. From the recommended data set for each reaction the average integrated cross section for a standard 14 MeV d(Be) neutron field was deduced. The spectrum-averaged cross section was also measured experimentally. A comparison of the integrated value with the integral measurement served to validate the excitation function within about 15%. A fast neutron source appears to be much more effective than a fission reactor for production of the above-mentioned radionuclides in a no-carrier-added form via the (n,p) process. In particular, the possibility of production of high specific activity {sup 153}Sm is discussed.

  16. Biophysical regulation of stem cell differentiation.

    Science.gov (United States)

    Govey, Peter M; Loiselle, Alayna E; Donahue, Henry J

    2013-06-01

    Bone adaptation to its mechanical environment, from embryonic through adult life, is thought to be the product of increased osteoblastic differentiation from mesenchymal stem cells. In parallel with tissue-scale loading, these heterogeneous populations of multipotent stem cells are subject to a variety of biophysical cues within their native microenvironments. Bone marrow-derived mesenchymal stem cells-the most broadly studied source of osteoblastic progenitors-undergo osteoblastic differentiation in vitro in response to biophysical signals, including hydrostatic pressure, fluid flow and accompanying shear stress, substrate strain and stiffness, substrate topography, and electromagnetic fields. Furthermore, stem cells may be subject to indirect regulation by mechano-sensing osteocytes positioned to more readily detect these same loading-induced signals within the bone matrix. Such paracrine and juxtacrine regulation of differentiation by osteocytes occurs in vitro. Further studies are needed to confirm both direct and indirect mechanisms of biophysical regulation within the in vivo stem cell niche.

  17. Biophysical shunt theory for neuropsychopathology: Part I.

    Science.gov (United States)

    Naisberg, Y; Avnon, M; Weizman, A

    1995-11-01

    We present a new model of the origin of schizophrenia based on biophysical ionic shunts in neuronal (electrical) pathways. Microstructural and molecular evidence is presented for the way in which changes in the neuronal membrane ionic channels may facilitate membrane property rearrangement, leading to a change in the density and composition of the ion channel charge which in turn causes a change in ionic flow orientation and distribution. We suggest that, under abnormal conditions, ionic flow shunts are created which redirect the biophysical collateral neuronal (electrical) pathways, resulting in psychiatric signs and symptoms. This model is complementary to the biological basis of schizophrenia.

  18. Global energy modeling - A biophysical approach

    Energy Technology Data Exchange (ETDEWEB)

    Dale, Michael

    2010-09-15

    This paper contrasts the standard economic approach to energy modelling with energy models using a biophysical approach. Neither of these approaches includes changing energy-returns-on-investment (EROI) due to declining resource quality or the capital intensive nature of renewable energy sources. Both of these factors will become increasingly important in the future. An extension to the biophysical approach is outlined which encompasses a dynamic EROI function that explicitly incorporates technological learning. The model is used to explore several scenarios of long-term future energy supply especially concerning the global transition to renewable energy sources in the quest for a sustainable energy system.

  19. Biophysical Evaluation of SonoSteam®:

    DEFF Research Database (Denmark)

    Andersen, Ann Zahle; Duelund, Lars; Brewer, Jonathan R.

    and safety evaluations. Our results show that there are no contradictions between data obtained by either approach. However, the biophysical methods draw a much more nuanced picture of the effects and efficiency of the investigated decontamination method, revealing e.g. an exponential dose/response...... relationship between SonoSteam treatment time and changes in collagen I, and a depth dependency in bacterial reduction, which points toward CFU counts overestimating total bacterial reduction. In conclusion the biophysical methods provide a less biased, reproducible and highly detailed system description...

  20. Process for encapsulating radionuclides

    International Nuclear Information System (INIS)

    Brownell, L.E.; Isaacson, R.E.

    1976-01-01

    Radionuclides are immobilized in virtually an insoluble form by reacting at a temperature of at least 90 0 C as an aqueous alkaline mixture having a solution pH of at least 10, containing a source of silicon, the radionuclide waste, and a metal cation. The molar ratio of silicon to the metal cation is on the order of unity to produce a gel from which complex metalosilicates crystallize to entrap the radionuclides within the resultant condensed crystal lattice. The product is a silicious stone-like material which is virtually insoluble and nonleachable in alkaline or neutral environment. One embodiment provides for the formation of the complex metalo-silicates, such as synthetic pollucite, by gel formation with subsequent calcination to the solid product; another embodiment utilizes a hydrothermal process, either above ground or deep within basalt caverns, at greater than atmospheric pressures and a temperature between 90 and 500 0 C to form complex metalo-silicates, such as strontium aluminosilicate. Another embodiment provides for the formation of complex metalo-silicates, such as synthetic pollucite, by slurrying an alkaline mixture of bentonite or kaolinite with a source of silicon and the radionuclide waste in salt form. In each of the embodiments a mobile system is achieved whereby the metalo-silicate constituents reorient into a condensed crystal lattice forming a cage structure with the condensed metalo-silicate lattice which completely surrounds the radionuclide and traps the radionuclide therein; thus rendering the radionuclide virtually insoluble

  1. Foodstuffs, radionuclides, monitoring

    International Nuclear Information System (INIS)

    Denisikov, A.I.

    2000-01-01

    Radionuclide contamination of water and food stuffs as a result of the Chernobyl accident and permissible contents of 90 Sr and 137 Cs are considered in brief. A method of radiation monitoring of food stuffs and water for the radionuclides mentioned is suggested. The method permits employment of the simplest and cheapest radiometric equipment for analysis, whole the high degree of radionuclide concentration using fiber sorbents permits using the instrumentation without expensive shields against external radiation. A description of ion-exchange unit for radiation monitoring of liquid samples of food stuffs or water, is provided [ru

  2. Generator for radionuclide

    International Nuclear Information System (INIS)

    Weisner, P.S.; Forrest, T.R.F.

    1985-01-01

    This invention provides a radionuclide generator of the kind in which a parent radionuclide, adsorbed on a column of particulate material, generates a daughter radionuclide which is periodically removed from the column. This invention is particularly concerned with technetium generators using single collection vials. The generator comprises a column, a first reservoir for the eluent, a second reservoir to contain the volume of eluent required for a single elution, and means connecting the first reservoir to the second reservoir and the second reservoir to the column. Such a generator is particularly suitable for operation by vacuum elution

  3. Biophysical aspects of cancer - Electromagnetic mechanism

    Czech Academy of Sciences Publication Activity Database

    Pokorný, Jiří; Hašek, Jiří; Vaniš, Jan; Jelínek, František

    2008-01-01

    Roč. 46, č. 5 (2008), s. 310-321 ISSN 0019-5189 Institutional research plan: CEZ:AV0Z20670512; CEZ:AV0Z50200510 Keywords : Electromagnetic Fields * Biophysics * Cancer Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.599, year: 2008

  4. Biophysics of Hair Cell Sensory Systems

    NARCIS (Netherlands)

    Duifhuis, Hendrikus; Horst, Johannes; van Dijk, Pim; van Netten, Sietse

    1993-01-01

    The last decade revealed to auditory researchers that hair cells can not only detect and process mechanical energy, but are also able to produce it. Thanks to the active hair cell, ears can produce otoacoustic emissions. This book gives the newest insights into the biophysics and physiology of

  5. Miscellaneous applications of radionuclide imaging

    International Nuclear Information System (INIS)

    Mishkin, F.S.; Freeman, L.M.

    1984-01-01

    The procedures discussed in this chapter are either developmental, in limited clinical use, or frankly moribund. A number of radionuclide imaging techniques have proved disappointing when approached from a purely anatomic point of view. This is particularly evident to our colleagues with the explosive growth of the noninvasive imaging procedures, magnetic resonance imaging (NMR), CT, and ultrasound, and the introduction of the less invasive digital radiographic approach to vascular opacification, all of which are capable of providing exquisite anatomic or tissue detail beyond the reach of current or reasonably priced nuclear medicine imaging systems. Yet, most nuclear medicine procedures possess the unique advantage of portraying a physiologic function without interfering with that function. Moreover, the procedures can be employed under conditions of stress, which are likely to bring out pathophysiologic abnormalities that remain masked when unchallenged. Information concerning form without functional data has less meaning than both together. The physiologic information inherent in nuclear medicine imaging may often provide not only key diagnostic information but also illuminate a therapeutic trail. Yet, it is often slighted in favor of the anatomic quest. While mastery of the nuances of imaging details remains critical, radionuclide image interpretation must rest upon a firm physiologic foundation. For this reason, this chapter emphasizes the physiologic approach

  6. Radionuclides in analytical chemistry

    International Nuclear Information System (INIS)

    Tousset, J.

    1984-01-01

    Applications of radionuclides in analytical chemistry are reviewed in this article: tracers, radioactive sources and activation analysis. Examples are given in all these fields and it is concluded that these methods should be used more widely [fr

  7. Radionuclide Basics: Iodine

    Science.gov (United States)

    ... Centers Radiation Protection Contact Us Share Radionuclide Basics: Iodine Iodine (chemical symbol I) is a chemical element. ... in the environment Iodine sources Iodine and health Iodine in the Environment All 37 isotopes of iodine ...

  8. Abscess detection with radionuclides

    International Nuclear Information System (INIS)

    Alavi, J.B.

    1988-01-01

    Radionuclide studies may aid in the diagnosis and localization of intra-abdominal infections. Despite the introduction of new radiographic and ultrasound methods, there are several clinical situations in which radionuclide scans have proved useful. Those include detection of postoperative intra-abdominal abscess, evaluation of liver abscess, differentiation between pancreatic pseudocyst or abscess, evaluation of fever of unknown origin, and evaluation of inflammatory bowel disease. Each clinical situation is discussed separately here

  9. Radionuclide fixation mechanisms in rocks

    International Nuclear Information System (INIS)

    Nakashima, S.

    1991-01-01

    In the safety evaluation of the radioactive waste disposal in geological environment, the mass balance equation for radionuclide migration is given. The sorption of radionuclides by geological formations is conventionally represented by the retardation of the radionuclides as compared with water movement. In order to quantify the sorption of radionuclides by rocks and sediments, the distribution ratio is used. In order to study quantitatively the long term behavior of waste radionuclides in geological environment, besides the distribution ratio concept in short term, slower radionuclide retention reaction involving mineral transformation should be considered. The development of microspectroscopic method for long term reaction path modeling, the behavior of iron during granite and water interaction, the reduction precipitation of radionuclides, radionuclide migration pathways, and the representative scheme of radionuclide migration and fixation in rocks are discussed. (K.I.)

  10. Biochemical and Biophysical Cues in Matrix Design for Chronic and Diabetic Wound Treatment.

    Science.gov (United States)

    Xiao, Yun; Ahadian, Samad; Radisic, Milica

    2017-02-01

    Progress in biomaterial science and engineering and increasing knowledge in cell biology have enabled us to develop functional biomaterials providing appropriate biochemical and biophysical cues for tissue regeneration applications. Tissue regeneration is particularly important to treat chronic wounds of people with diabetes. Understanding and controlling the cellular microenvironment of the wound tissue are important to improve the wound healing process. In this study, we review different biochemical (e.g., growth factors, peptides, DNA, and RNA) and biophysical (e.g., topographical guidance, pressure, electrical stimulation, and pulsed electromagnetic field) cues providing a functional and instructive acellular matrix to heal diabetic chronic wounds. The biochemical and biophysical signals generally regulate cell-matrix interactions and cell behavior and function inducing the tissue regeneration for chronic wounds. Some technologies and devices have already been developed and used in the clinic employing biochemical and biophysical cues for wound healing applications. These technologies can be integrated with smart biomaterials to deliver therapeutic agents to the wound tissue in a precise and controllable manner. This review provides useful guidance in understanding molecular mechanisms and signals in the healing of diabetic chronic wounds and in designing instructive biomaterials to treat them.

  11. Radioactivity: radionuclides in foods

    International Nuclear Information System (INIS)

    Simpson, R.E.; Baratta, E.J.; Jelinek, C.F.

    1977-01-01

    The results are summarized of the analysis for strontium-90, cesium-137, iodine-131, ruthenium-106, and potassium-40, a naturally occurring radionuclide, in samples of total diet and selected import commodities in the foods compliance program of the Food and Drug Administration. On the basis of the radionuclide intake guidelines established by the Federal Radiation Council (FRC), the low content of radionuclides found in the total diet samples for fiscal years 1973 and 1974 demonstrates the need for surveillance only at the present level. The low levels of radionuclides found in a limited number of edible imported commodities indicate that their contribution to the total diet would not increase the levels of these radionuclides above those recommended for only periodic surveillance by the FRC. The potassium levels, determined from potassium-40 activity, found in meats and fish agree with the value for normal muscle tissue for the reference man reported by the International Commission on Radiation Protection. Of the other commodities, nuts contained the highest levels, while sugar, beverages, and processed foods contained the lowest levels of potassium. Although cesium and potassium are chemical analogs with similar metabolic properties, because of their variable content in some leafy samples as a result of surface contamination, a correlation between cesium-137 levels and the cesium-137-to-potassium ratio was inconclusive

  12. Handbook of Single-Molecule Biophysics

    CERN Document Server

    Hinterdorfer, Peter

    2009-01-01

    The last decade has seen the development of a number of novel biophysical methods that allow the manipulation and study of individual biomolecules. The ability to monitor biological processes at this fundamental level of sensitivity has given rise to an improved understanding of the underlying molecular mechanisms. Through the removal of ensemble averaging, distributions and fluctuations of molecular properties can be characterized, transient intermediates identified, and catalytic mechanisms elucidated. By applying forces on biomolecules while monitoring their activity, important information can be obtained on how proteins couple function to structure. The Handbook of Single-Molecule Biophysics provides an introduction to these techniques and presents an extensive discussion of the new biological insights obtained from them. Coverage includes: Experimental techniques to monitor and manipulate individual biomolecules The use of single-molecule techniques in super-resolution and functional imaging Single-molec...

  13. Biophysical behavior of Scomberoides commersonianus skin collagen.

    Science.gov (United States)

    Kolli, Nagamalleswari; Joseph, K Thomas; Ramasami, T

    2002-06-01

    Some biophysical characteristics of the skin collagen from Scomberoides commersonianus were measured and compared to those of rat tail tendon. Stress-strain data indicate that the strain at break as well as the tensile strength of the fish skin without scales increased significantly. The maximum tension in case of rat skin is at least a factor of two higher than that observed in fish skin. The much lower hydrothermal isometric tension measurements observed in fish skin are attributable to a lesser number of heat stable crosslinks. Stress relaxation measurements in the fish skin indicate that more than one relaxation process may be involved in the stabilization of collagenous matrix. The observed differences in the biophysical behavior of fish skin may well arise from combination of changes in extent of hydroxylation of proline in collagen synthesis, hydrogen bond network and fibril orientation as compared to rat tail tendon.

  14. Biophysics and the Challenges of Emerging Threats

    CERN Document Server

    Puglisi, Joseph D

    2009-01-01

    This volume is a collection of articles from the proceedings of the International School of Structural Biology and Magnetic Resonance 8th Course: Biophysics and the Challenges of Emerging Threats. This NATO Advance Study Institute (ASI) was held in Erice at the Ettore Majorana Foundation and Centre for Scientific Culture on 19 through 30 June 2007. The ASI brought together a diverse group of experts who bridged the fields of virology and biology, biophysics, chemistry and physics. Prominent lecturers and students from around the world representant a total of 24 countries participated in the NATO ASI organized by Professors Joseph Puglisi (Stanford University, USA) and Alexander Arseniev (Moscow, RU). The central hypothesis underlying this ASI was that interdisciplinary research, merging principles of physics, chemistry and biology, can drive new discovery in detecting and fighting bioterrorism agents, lead to cleaner environments, and help propel development in NATO partner countries. The ASI merged the relat...

  15. Trends in cyclotrons for radionuclide production

    International Nuclear Information System (INIS)

    Vera Ruiz, H.; Lambrecht, R.M.

    1999-01-01

    The IAEA recently concluded a worldwide survey of the cyclotrons used for radionuclide production. Most of the institutions responded to the questionnaire. The responses identified technical, utilisation and administrative information for 206 cyclotrons. Compiled data includes the characteristics, performance and popularity of each of the different commercial cyclotrons. Over 20 cyclotrons are scheduled for installation in 1998. The expansion in the number of cyclotron installations during the last decade was driven by the advent of advances in medical imaging instrumentation (namely, positron emission tomography (PET), and more recently by 511 KeV emission tomography); introduction of user friendly compact medical cyclotrons; and recent governmental decisions that permit reimbursement for cyclotron radiopharmaceutical studies by the government or insurance companies. The priorities for the production of clinical, commercial and research radionuclides were identified. The emphasis is on radionuclides used for medical diagnosis with SPET (e.g. 123 I, 201 Tl) and PET (e.g. 11 C, 13 N, 15 O, 18 F) radiopharmaceuticals, and for individualized patient radiation treatment planning (e.g. 64 Cu, 86 Y, 124 I) with PET. There is an emerging trend to advance the cyclotron as an alternative method to nuclear reactors for the production of neutron-rich radionuclides (e.g. 64 Cu, 103 Pd, 186 Re) needed for therapeutic applications. (authors)

  16. The development and use of radionuclide generators in nuclear medicine - recent advances and future perspectives

    International Nuclear Information System (INIS)

    Knapp, F.F. Jr.

    1998-03-01

    Although the trend in radionuclide generator research has declined, radionuclide generator systems continue to play an important role in nuclear medicine. Technetium-99m obtained from the molybdenum-99/technetium-99m generator system is used in over 80% of all diagnostic clinical studies and there is increasing interest and use of therapeutic radioisotopes obtained from generator systems. This paper focuses on a discussion of the major current areas of radionuclide generator research, and the expected areas of future research and applications

  17. Radionuclides in house dust

    CERN Document Server

    Fry, F A; Green, N; Hammond, D J

    1985-01-01

    Discharges of radionuclides from the British Nuclear Fuel plc (BNFL) reprocessing plant at Sellafield in Cumbria have led to elevated concentrations radionuclides in the local environment. The major routes of exposure of the public are kept under review by the appropriate Government departments and monitoring is carried out both by the departments and by BNFL itself. Recently, there has been increasing public concern about general environmental contamination resulting from the discharges and, in particular, about possible exposure of members of the public by routes not previously investigated in detail. One such postulated route of exposure that has attracted the interest of the public, the press and Parliament arises from the presence of radionuclides within houses. In view of this obvious and widespread concern, the Board has undertaken a sampling programme in a few communities in Cumbria to assess the radiological significance of this source of exposure. From the results of our study, we conclude that, alt...

  18. Tumour therapy with radionuclides: assessment of progress and problems

    International Nuclear Information System (INIS)

    Carlsson, Joergen; Forssell Aronsson, Eva; Hietala, Sven-Ola; Stigbrand, Torgny; Tennvall, Jan

    2003-01-01

    Radionuclide therapy is a promising modality for treatment of tumours of haematopoietic origin while the success for treatment of solid tumours so far has been limited. The authors consider radionuclide therapy mainly as a method to eradicate disseminated tumour cells and small metastases while bulky tumours and large metastases have to be treated surgically or by external radiation therapy. The promising therapeutic results for haematological tumours give hope that radionuclide therapy will have a breakthrough also for treatment of disseminated cells from solid tumours. New knowledge related to this is continuously emerging since new molecular target structures are being characterised and the knowledge on pharmacokinetics and cellular processing of different types of targeting agents increases. There is also improved understanding of the factors of importance for the choice of appropriate radionuclides with respect to their decay properties and the therapeutic applications. Furthermore, new methods to modify the uptake of radionuclides in tumour cells and normal tissues are emerging. However, we still need improvements regarding dosimetry and treatment planning as well as an increased knowledge about the tolerance doses for normal tissues and the radiobiological effects on tumour cells. This is especially important in targeted radionuclide therapy where the dose rates often are lower than 1 Gy/h

  19. Radionuclides in foods

    International Nuclear Information System (INIS)

    1994-01-01

    This report contains data on the levels of radionuclides in the UK foodchain. Most data derive from monitoring programmes that exist around nuclear sites, and in some cases date back to the 1960s. Some comparative data from site operator and government-run programmes are included. Data from monitoring undertaken after the Chernobyl accident are summarised. General monitoring of the foodchain for both artificial and natural radionuclides, and the results of relevant government-sponsored research are also described. The report includes basic information on radioactivity in the environment, radiation protection standards and describes what measures are taken to routinely monitor the foodchain and assess public risk. (Author)

  20. Targeted Radionuclide Therapy

    Directory of Open Access Journals (Sweden)

    David Cheng

    2011-10-01

    Full Text Available Targeted radiotherapy is an evolving and promising modality of cancer treatment. The killing of cancer cells is achieved with the use of biological vectors and appropriate radionuclides. Among the many advantages of this approach are its selectiveness in delivering the radiation to the target, relatively less severe and infrequent side effects, and the possibility of assessing the uptake by the tumor prior to the therapy. Several different radiopharmaceuticals are currently being used by various administration routes and targeting mechanisms. This article aims to briefly review the current status of targeted radiotherapy as well as to outline the advantages and disadvantages of radionuclides used for this purpose.

  1. Targeted Radionuclide Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Ersahin, Devrim, E-mail: devrimersahin@yahoo.com; Doddamane, Indukala; Cheng, David [Department of Diagnostic Radiology, School of Medicine, Yale University, 333 Cedar St., New Haven, CT 06520 (United States)

    2011-10-11

    Targeted radiotherapy is an evolving and promising modality of cancer treatment. The killing of cancer cells is achieved with the use of biological vectors and appropriate radionuclides. Among the many advantages of this approach are its selectiveness in delivering the radiation to the target, relatively less severe and infrequent side effects, and the possibility of assessing the uptake by the tumor prior to the therapy. Several different radiopharmaceuticals are currently being used by various administration routes and targeting mechanisms. This article aims to briefly review the current status of targeted radiotherapy as well as to outline the advantages and disadvantages of radionuclides used for this purpose.

  2. Radionuclide deposition control

    International Nuclear Information System (INIS)

    1980-01-01

    A method is described for controlling the deposition, on to the surfaces of reactor components, of the radionuclides manganese-54, cobalt-58 and cobalt-60 from a liquid stream containing the radionuclides. The method consists of disposing a getter material (nickel) in the liquid stream, and a non-getter material (tantalum, tungsten or molybdenum) as a coating on the surfaces where deposition is not desired. The process is described with special reference to its use in the coolant circuit in sodium cooled fast breeder reactors. (U.K.)

  3. Radionuclide examination in rheumatology

    International Nuclear Information System (INIS)

    Streda, A.; Kolar, J.; Valesova, M.

    1984-01-01

    On the basis of twenty years of experience with the use of radionuclides in bone and articular rheumatic diseases indications for such examinations are summed up. The main advantage of the use of radionuclide methods is that they bring forward early diagnosis of tissue reconstruction which can thus be detected at the stage of microstructural changes. They also provide earlier and more reliable detection of the degree of the pathological process than is provided by X-ray examination. In some cases scintiscan may also be found useful as a method for following up the results of treatment of rheumatic diseases. (author)

  4. Targeted Radionuclide Therapy

    International Nuclear Information System (INIS)

    Ersahin, Devrim; Doddamane, Indukala; Cheng, David

    2011-01-01

    Targeted radiotherapy is an evolving and promising modality of cancer treatment. The killing of cancer cells is achieved with the use of biological vectors and appropriate radionuclides. Among the many advantages of this approach are its selectiveness in delivering the radiation to the target, relatively less severe and infrequent side effects, and the possibility of assessing the uptake by the tumor prior to the therapy. Several different radiopharmaceuticals are currently being used by various administration routes and targeting mechanisms. This article aims to briefly review the current status of targeted radiotherapy as well as to outline the advantages and disadvantages of radionuclides used for this purpose

  5. New radionuclide generator systems for use in nuclear medicine

    International Nuclear Information System (INIS)

    Atcher, R.W.

    1979-01-01

    A current emphasis in nuclear medicine is to better match the physical lifetime of the radionuclides used in vivo for diagnosis and treatment to the biological lifetime of the diagnostic procedure or to minimize radiation dose to areas other than those to be treated. In many cases the biological lifetime is on the order of minutes. Since the direct production of radionuclides with half lives of minutes requires the user to be near a suitable reactor or accelerator, this study was undertaken to produce short-lived radionuclides indirectly. If a long-lived radionuclide decays into a short-lived radionuclide, quick separation of the daughter activity from the parent enables the user to have a short-lived daughter while freeing him from the constraint of proximity to a cyclotron. Systems where a short-lived daughter is separated from a long-lived parent are called radionuclide generators. Two generator systems were developed for use in nuclear medicine, one in diagnostic work and the other for therapeutic work. The yield and breakthrough characteristics were within the limits required to minimize unnecessary radiation exposure in patients. Two parent radionuclides were produced using 4 He beams available from medium energy cyclotrons. The yield was high enough to produce generators that would be useful in clinical applications

  6. Radionuclide synovectomy – essentials for rheumatologists

    Directory of Open Access Journals (Sweden)

    Marek M. Chojnowski

    2016-07-01

    Full Text Available Radionuclide synovectomy is a minimally invasive method of treating persistent joint inflammation. It involves intra-articular injection of radioactive colloids which induce necrosis and fibrosis of hypertrophic synovial membrane. The most common indication for radiosynovectomy is rheumatoid arthritis, although patients with seronegative spondyloarthropathies, unclassified arthritis, haemophilic arthropathy and other less common arthropathies can also benefit from this method. Radiosynovectomy is safe, well tolerated and efficacious. About 70–80% of patients respond well to the therapy. However, the therapeutic effects are considerably worse in patients with co-existent osteoarthritis and advanced joint degeneration. Despite its advantages, radionuclide synovectomy is not performed as often as it could be, so greater knowledge and understanding of this method are needed. The authors present the most important facts about radiosynovectomy that may help rheumatologists in their daily clinical practice.

  7. Report on the 1st research co-ordination meeting of the co-ordinated research project on standardized high current solid targets for cyclotron production of diagnostic and therapeutic radionuclides

    International Nuclear Information System (INIS)

    2000-01-01

    Radioisotopes produced with a cyclotron and their corresponding radiopharmaceuticals have already been shown to be extremely valuable in basic medical research, disease diagnosis and radiotherapy treatment. There are more than 200 cyclotron facilities worldwide and the number is growing every year. A number of the Member States have acquired cyclotrons for the purpose of producing radioisotopes for nuclear medicine and a number of others have expressed an interest in acquiring such facilities. This report is concerned with the production of four radiotracers: Iodine-123, Iodine-124, Thallium-201 and Palladium-103. Iodine-123 is already widely used in SPECT studies, I-124 has shown great promise and can be used for PET studies as well as in radiotherapy. Tl-201 is widely used throughout the world as 201 Tl + for measuring cardiac blood flow. It is a routine tool that is needed for the Nuclear Medicine communities and can be made available by those countries possessing a cyclotron facility with 30 MeV protons. Moreover, as preliminary results dealing with the labelling of chelated polypeptides with trivalent cationic Tl-201 are very promising; the nuclide can also be tried as a potential substitute for Indium tracers in SPECT diagnosis involving polypeptides. Palladium-103, an Auger electron emitter, has become an extremely important radionuclide for therapy. The Co-ordinated Research Programme (CRP) focuses on the optimisation and standardisation of solid phase cyclotron target technology for the production of I-123, I-124, Tl-201 and Pd-103. In particular, as originally proposed and further discussed and agreed upon during the 1st Research Co-ordination Meeting, the main technical goals of the CRP are described as follows: (i) to investigate the possibility of using electrodeposited tellurium and melted tellurium oxide as target material for the production of I-123 and I-124. For the oxide target, the following parameters and techniques will be explored: 1) methods

  8. Taking radionuclides to heart

    International Nuclear Information System (INIS)

    Kleynhans, P.H.T.; Lotter, M.G.; Van Aswegen, A.; Minnaar, P.C.; Iturralde, M.; Herbst, C.P.; Marx, D.

    1980-01-01

    Ischaemic heart disease is a main cause of death in South Africa. Non-invasive ECG gated radionuclide bloodpool imaging plays an increasingly useful role in the evalution of the function of the heart as a pump, and the extent of heart muscle perfusion defects is further pinpointed by invasive krypton-81m studies to improve patient management

  9. Radionuclides deposition over Antarctica

    International Nuclear Information System (INIS)

    Pourchet, M.; Magand, O.; Frezzotti, M.; Ekaykin, A.; Winther, J.-G.

    2003-01-01

    A detailed and comprehensive map of the distribution patterns for both natural and artificial radionuclides over Antarctica has been established. This work integrates the results of several decades of international programs focusing on the analysis of natural and artificial radionuclides in snow and ice cores from this polar region. The mean value (37±20 Bq m -2 ) of 241 Pu total deposition over 28 stations is determined from the gamma emissions of its daughter 241 Am, presenting a long half-life (432.7 yrs). Detailed profiles and distributions of 241 Pu in ice cores make it possible to clearly distinguish between the atmospheric thermonuclear tests of the fifties and sixties. Strong relationships are also found between radionuclide data ( 137 Cs with respect to 241 Pu and 210 Pb with respect to 137 Cs), make it possible to estimate the total deposition or natural fluxes of these radionuclides. Total deposition of 137 Cs over Antarctica is estimated at 760 TBq, based on results from the 90-180 deg. East sector. Given the irregular distribution of sampling sites, more ice cores and snow samples must be analyzed in other sectors of Antarctica to check the validity of this figure

  10. Soil burden by radionuclides

    International Nuclear Information System (INIS)

    Blum, W.E.H.; Wenzel, W.W.

    1989-01-01

    Natural radioactivity - half-lifes and radiation type of man-made nuclides, radionuclide behaviour in soils, effects on soil condition and soil functions are described. The only mode of decontamination is by decay and thus primarily dependent on the half-life of nuclides

  11. Radionuclides in house dust

    Energy Technology Data Exchange (ETDEWEB)

    Fry, F A; Green, N; Dodd, N J; Hammond, D J

    1985-04-01

    Discharges of radionuclides from the British Nuclear Fuel plc (BNFL) reprocessing plant at Sellafield in Cumbria have led to elevated concentrations radionuclides in the local environment. The major routes of exposure of the public are kept under review by the appropriate authorising Government departments and monitoring is carried out both by the departments and by BNFL itself. Recently, there has been increasing public concern about general environmental contamination resulting from the discharges and, in particular, about possible exposure of members of the public by routes not previously investigated in detail. One such postulated route of exposure that has attracted the interest of the public, the press and Parliament arises from the presence of radionuclides within houses. In view of this obvious and widespread concern, the Board has undertaken a sampling programme in a few communities in Cumbria to assess the radiological significance of this source of exposure. From the results of our study, we conclude that, although radionuclides originating rom the BNFL site can be detected in house dust, this source of contamination is a negligible route of exposure for members of the public in West Cumbria. This report presents the results of the Board's study of house dust in twenty homes in Cumbria during the spring and summer of 1984. A more intensive investigation is being carried out by Imperial College. (author)

  12. Radionuclide body function imager

    International Nuclear Information System (INIS)

    Stoddart, H.F.

    1983-01-01

    A transverse radionuclide scan field imaging apparatus is claimed. It comprises: a plurality of highly focused closely laterally adjacent collimators arranged inwardly focused in an array which surrounds a scan field, each collimator being moveable relative to its adjacent collimator; means for rotating the array about the scan field and means for imparting travel to the collimators

  13. Biophysical EPR Studies Applied to Membrane Proteins

    Science.gov (United States)

    Sahu, Indra D; Lorigan, Gary A

    2015-01-01

    Membrane proteins are very important in controlling bioenergetics, functional activity, and initializing signal pathways in a wide variety of complicated biological systems. They also represent approximately 50% of the potential drug targets. EPR spectroscopy is a very popular and powerful biophysical tool that is used to study the structural and dynamic properties of membrane proteins. In this article, a basic overview of the most commonly used EPR techniques and examples of recent applications to answer pertinent structural and dynamic related questions on membrane protein systems will be presented. PMID:26855825

  14. Synchrotron radiation applications in biophysics and medicine

    International Nuclear Information System (INIS)

    Burattini, E.

    1985-01-01

    The peculiar properties of synchrotron radiation are briefly summarized. A short review on the possible applications of synchrotron radiation in two important fields like Biophysics and Medicine is presented. Details are given on experiments both in progress and carried out in many synchrotron radiation facilities, all over the world, using different techniques like X-ray absorption and fluorescence spectroscopy, X-ray fluorescence microanalysis, X-ray microscopy and digital subtraction angiography. Some news about the photon-activation therapy are briefly reported too

  15. Biophysical processes in the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Mc; Murtugudde, R.; Vialard, J.; Vinayachandran, P.N.; Wiggert, J.D.; Hood, R.R.; Shankar, D.; Shetye, S.R.

    Ocean Biogeochemical Processes and Ecological Variability Geophysical Monograph Series 185 Copyright 200� by the American Geophysical Union. 10.102�/2008GM000768 Biophysical Processes in the Indian Ocean J. P. McCreary, 1 R. Murtugudde, 2 J. Vialard, 3...) also plots the upper-layer thickness, h 1 , from the model of McCreary et al. [1��3] (hereinafter referred to as MKM); h 1 simulates the structure of the top of the actual thermocline reasonably well, except that it is somewhat too thin from 5...

  16. Radionuclide cardiography in medical practice

    International Nuclear Information System (INIS)

    Strangfeld, D.; Mohnike, W.; Schmidt, J.; Heine, H.; Correns, H.J.

    1986-01-01

    This publication is a compendium on all aspects of radionuclide diagnostics concerning cardiovascular system diseases. Starting with introductory remarks on the control of cardiovascular diseases the contribution of radionuclide cardiology to functional cardiovascular diagnostics as well as pathophysiological and pathobiochemical aspects of radiocardiography are outlined. Radiopharmaceuticals used in radiocardiography, physical and technical problems in application of radionuclides and their measuring techniques are discussed. In individual chapters radionuclide ventriculography, myocardial scintiscanning, circulatory diagnostics, radionuclide diagnostics of arterial hypertension, of thrombosis and in vitro diagnostics of thrombophilia are treated in the framework of clinical medicine

  17. Radiation fields, dosimetry, biokinetics and biophysical models for cancer induction by ionising radiation 1996-1999. Executive summary

    International Nuclear Information System (INIS)

    Jacob, P.; Paretzke, H.G.; Roth, P.

    2000-01-01

    The Association Contract covers a range of research domains that are important to the Radiation Protection Research Action, especially in the areas 'Evaluation of Radiation Risks' and 'Understanding Radiation Mechanisms and Epidemiology'. Three research projects concentrate on radiation dosimetry research and two projects on the modelling of radiation carcinogenesis. The following list gives an overview on the topics and responsible scientific project leaders of the Association Contract: Study of radiation fields and dosimetry at aviation altitudes. Biokinetics and dosimetry of incorporated radionuclides. Dose reconstruction. Biophysical models for the induction of cancer by radiation. Experimental data for the induction of cancer by radiation of different qualities. (orig.)

  18. Radionuclides in food

    International Nuclear Information System (INIS)

    Fernandez Gomez, Isis Maria

    2008-01-01

    The sources of the presence of radionuclides in food are presented: natural radiation and artificial radiation. The transfer of radionuclides through food chains, intakes of radionuclides to the body with its partners effective doses and typical consumption of basic foods of a rural adult population are exposed as main topics. Also the radiation doses from natural sources and exposure to man by ingestion of contaminated food with radionuclides of artificial origin are shown. The contribution of the food ingestion to the man exposure depends on: characteristics of radionuclide, natural conditions, farming practices and eating habits of the population. The principal international organizations in charge of setting guide levels for radionuclides in food are mentioned: standards, rules and the monitoring. It establishes that a guide is necessary for the food monitoring; the alone CODEX ALIMENTARIUS is applicable to emergency situations and the generic action levels proposed by the CODEX not satisfy all needs (no guiding international levels for planned or existing situations such as NORM). There are handled mainly socio-economic and political aspects. Among the actions to be taken are: to assure a public comprehensive information over the risk evaluation in food; to reinforce the collaboration among the different international organizations (WHO, IAEA, ICRP, EC) in relation with the food of set; to give follow-up to the control of the drinkable water and NORM's presence in the food. In addition, it is possible to create the necessary mechanisms to reduce the number of irrelevant measures and bureaucratic useless steps (certificates); to promote the exchange between the different institutions involved in the topic of the food, with relation to the acquired experiences and learned lessons. Likewise, it might examine the possibility of a multidisciplinary approximation (radioactive and not radioactive pollutants); to elaborate a technical guide to assure the

  19. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    J. Prouty

    2006-01-01

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

  20. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    J. Prouty

    2006-07-14

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment (TSPA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers advective transport and diffusive transport

  1. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    Schreiner, R.

    2001-01-01

    The purpose of this work is to develop the Engineered Barrier System (EBS) radionuclide transport abstraction model, as directed by a written development plan (CRWMS M and O 1999a). This abstraction is the conceptual model that will be used to determine the rate of release of radionuclides from the EBS to the unsaturated zone (UZ) in the total system performance assessment-license application (TSPA-LA). In particular, this model will be used to quantify the time-dependent radionuclide releases from a failed waste package (WP) and their subsequent transport through the EBS to the emplacement drift wall/UZ interface. The development of this conceptual model will allow Performance Assessment Operations (PAO) and its Engineered Barrier Performance Department to provide a more detailed and complete EBS flow and transport abstraction. The results from this conceptual model will allow PA0 to address portions of the key technical issues (KTIs) presented in three NRC Issue Resolution Status Reports (IRSRs): (1) the Evolution of the Near-Field Environment (ENFE), Revision 2 (NRC 1999a), (2) the Container Life and Source Term (CLST), Revision 2 (NRC 1999b), and (3) the Thermal Effects on Flow (TEF), Revision 1 (NRC 1998). The conceptual model for flow and transport in the EBS will be referred to as the ''EBS RT Abstraction'' in this analysis/modeling report (AMR). The scope of this abstraction and report is limited to flow and transport processes. More specifically, this AMR does not discuss elements of the TSPA-SR and TSPA-LA that relate to the EBS but are discussed in other AMRs. These elements include corrosion processes, radionuclide solubility limits, waste form dissolution rates and concentrations of colloidal particles that are generally represented as boundary conditions or input parameters for the EBS RT Abstraction. In effect, this AMR provides the algorithms for transporting radionuclides using the flow geometry and radionuclide concentrations determined by other

  2. Initial Radionuclide Inventories

    Energy Technology Data Exchange (ETDEWEB)

    H. Miller

    2004-09-19

    The purpose of this analysis is to provide an initial radionuclide inventory (in grams per waste package) and associated uncertainty distributions for use in the Total System Performance Assessment for the License Application (TSPA-LA) in support of the license application for the repository at Yucca Mountain, Nevada. This document is intended for use in postclosure analysis only. Bounding waste stream information and data were collected that capture probable limits. For commercially generated waste, this analysis considers alternative waste stream projections to bound the characteristics of wastes likely to be encountered using arrival scenarios that potentially impact the commercial spent nuclear fuel (CSNF) waste stream. For TSPA-LA, this radionuclide inventory analysis considers U.S. Department of Energy (DOE) high-level radioactive waste (DHLW) glass and two types of spent nuclear fuel (SNF): CSNF and DOE-owned (DSNF). These wastes are placed in two groups of waste packages: the CSNF waste package and the codisposal waste package (CDSP), which are designated to contain DHLW glass and DSNF, or DHLW glass only. The radionuclide inventory for naval SNF is provided separately in the classified ''Naval Nuclear Propulsion Program Technical Support Document'' for the License Application. As noted previously, the radionuclide inventory data presented here is intended only for TSPA-LA postclosure calculations. It is not applicable to preclosure safety calculations. Safe storage, transportation, and ultimate disposal of these wastes require safety analyses to support the design and licensing of repository equipment and facilities. These analyses will require radionuclide inventories to represent the radioactive source term that must be accommodated during handling, storage and disposition of these wastes. This analysis uses the best available information to identify the radionuclide inventory that is expected at the last year of last emplacement

  3. Therapeutic applications of radiopharmaceuticals

    International Nuclear Information System (INIS)

    Baker, W.J.; Datz, F.L.; Beightol, R.W.

    1987-01-01

    Whether a radiopharmaceutical has diagnostic or therapeutic application depends on both the isotope and pharmaceutical used. For diagnostic applications, the isotope should undergo only γ-decay, since usually only γ-radiation is detected by nuclear medicine cameras. The half-life should be just long enough to allow the procedure to be performed. In contrast, the isotope needed for therapeutic purposes should have particulate radiation, such as a β-particle (electron), since these are locally absorbed an increase the local radiation dose. γ-Radiation, which penetrates the tissues, produces less radiation dose than do Β-particles. Several references dealing with radioactive decay, particulate interactions, and diagnostic and therapeutic applications of radiopharmaceuticals are available. Radiopharmaceuticals can legally be used only by physicians who are qualified by specific training in the safe handling of radionuclides. The experience and training of these physicians must be approved by the Nuclear Regulatory Commission or Agreement State Agency authorized to license the use of radiopharmaceuticals. A list of all byproduct material and procedures is available in the Code of Federal Regulations. Of the many radiopharmaceuticals available for diagnostic and therapeutic use, only those commonly used are discussed in this chapter

  4. Biophysical and lipofection studies of DOTAP analogs.

    Science.gov (United States)

    Regelin, A E; Fankhaenel, S; Gürtesch, L; Prinz, C; von Kiedrowski, G; Massing, U

    2000-03-15

    In order to investigate the relationship between lipid structure and liposome-mediated gene transfer, we have studied biophysical parameters and transfection properties of monocationic DOTAP analogs, systematically modified in their non-polar hydrocarbon chains. Stability, size and (by means of anisotropy profiles) membrane fluidity of liposomes and lipoplexes were determined, and lipofection efficiency was tested in a luciferase reporter gene assay. DOTAP analogs were used as single components or combined with a helper lipid, either DOPE or cholesterol. Stability of liposomes was a precondition for formation of temporarily stable lipoplexes. Addition of DOPE or cholesterol improved liposome and lipoplex stability. Transfection efficiencies of lipoplexes based on pure DOTAP analogs could be correlated with stability data and membrane fluidity at transfection temperature. Inclusion of DOPE led to rather uniform transfection and anisotropy profiles, corresponding to lipoplex stability. Cholesterol-containing lipoplexes were generally stable, showing high transfection efficiency at low relative fluidity. Our results demonstrate that the efficiency of gene transfer mediated by monocationic lipids is greatly influenced by lipoplex biophysics due to lipid composition. The measurement of fluorescence anisotropy is an appropriate method to characterize membrane fluidity within a defined system of liposomes or lipoplexes and may be helpful to elucidate structure-activity relationships.

  5. A mathematical approach to protein biophysics

    CERN Document Server

    Scott, L Ridgway

    2017-01-01

    This book explores quantitative aspects of protein biophysics and attempts to delineate certain rules of molecular behavior that make atomic scale objects behave in a digital way.  This book will help readers to understand how certain biological systems involving proteins function as digital information systems despite the fact that underlying processes are analog in nature. The in-depth explanation of proteins from a quantitative point of view and the variety of level of exercises (including physical experiments) at the end of each chapter will appeal to graduate and senior undergraduate students in mathematics, computer science, mechanical engineering, and physics, wanting to learn about the biophysics of proteins.  L. Ridgway Scott has been Professor of Computer Science and of Mathematics at the University of Chicago since 1998, and the Louis Block Professor since 2001.  He obtained a B.S. degree (Magna Cum Laude) from Tulane University in 1969 and a PhD degree in Mathematics from the Massachusetts Ins...

  6. Radionuclide esophageal emptying study before and after pneumatic dilatation in achalasia

    Energy Technology Data Exchange (ETDEWEB)

    Ujiie, Hiroaki; Hongo, Michio; Lin, Yih-Fong; Satake, Kenzo; Asaki, Shigeru; Goto, Yoshio; Okuyama, Shinichi

    1987-11-01

    The therapeutic effect of pneumatic dilatation was evaluated quantitatively by radionuclide transit study in 11 achalasia patients. Before pneumatic dilatation, marked retention with more than 80 % of isotope in the esophagus at 15 minutes after ingestion was noted in all patients. Marked improvement in emptying was shown after pneumatic dilatation. Pneumatic dilatation is a safe and effective therapeutic aid for achalasia treatment, and radionuclide transit study is not only noninvasive and physiologic but also its procedure is easily performed. We conclude that radionuclide transit study is a good method to evaluate the result of the treatment quantitatively in achalasia patients.

  7. Fukushima Daiichi Radionuclide Inventories

    Energy Technology Data Exchange (ETDEWEB)

    Cardoni, Jeffrey N. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Jankovsky, Zachary Kyle [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2016-09-01

    Radionuclide inventories are generated to permit detailed analyses of the Fukushima Daiichi meltdowns. This is necessary information for severe accident calculations, dose calculations, and source term and consequence analyses. Inventories are calculated using SCALE6 and compared to values predicted by international researchers supporting the OECD/NEA's Benchmark Study on the Accident at Fukushima Daiichi Nuclear Power Station (BSAF). Both sets of inventory information are acceptable for best-estimate analyses of the Fukushima reactors. Consistent nuclear information for severe accident codes, including radionuclide class masses and core decay powers, are also derived from the SCALE6 analyses. Key nuclide activity ratios are calculated as functions of burnup and nuclear data in order to explore the utility for nuclear forensics and support future decommissioning efforts.

  8. Radionuclide table. Pt. 1

    International Nuclear Information System (INIS)

    Legrand, Jean; Perolat, J.-P.; Lagoutine, Frederic; Le Gallic, Yves.

    The evaluation of the following 29 radionuclides is presented: 22 Na, 24 Na, sup(24m)Na, 51 Cr, 54 Mn, 57 Co, 58 Co, sup(58m)Co, 60 Co, sup(60m)Co, 75 Se, 103 Ru, sup(103m)Rh, sup(110m)Ag- 110 Ag, 109 Cd, 125 Sb, sup(125mTe), 125 I, 133 Xe, sup(133m)Xe, 131 Cs, 134 Cs, sup(134m)Cs, 139 Ce, 144 Ce- 144 Pr, 144 Pr, 169 Er, 186 Re, 203 Hg. The introduction contains a brief description of radioactive processes and the evaluation rules followed. The best values and associated uncertainties are given for each radionuclide for the major parameters of the decay scheme and the radiation intensities emitted, together with a decay table. Gamma, X-rays and sometimes conversion electron spectra are also provided [fr

  9. Radionuclide co-precipitation

    International Nuclear Information System (INIS)

    Bruno, J.; Sandino, A.

    1987-12-01

    The thermodynamic and kinetic behaviour of the minor components of the spent fuel matrix has been theoretically and experimentally investigated. Two different situations have been studied: Part I, the near field scenario, where the release and migration of the minor components is dependent on the solubility behaviour of UO 2 (s); Part II, the far field, where the solubility and transport of the radionuclides is related to the major geochemical processes occurring. (orig.)

  10. Radionuclide fate and effects

    International Nuclear Information System (INIS)

    Anon.

    1983-01-01

    The studies reported here deal with the full range of contaminant behavior and fate, from the initial physicochemical factors that govern radionuclide availability in terrestrial and aquatic environments to studies of contaminant transport by biological means. By design, we focus more on the biologically and chemically mediated transport processes and food-chain pathways than on the purely physical forms of contaminant transport, such as transport by wind and water

  11. Geochemistry and radionuclide migration

    International Nuclear Information System (INIS)

    Isherwood, D.

    1978-01-01

    Theoretically, the geochemical barrier can provide a major line of defense in protecting the biosphere from the hazards of nuclear waste. The most likely processes involved are easily identified. Preliminary investigations using computer modeling techniques suggest that retardation is an effective control on radionuclide concentrations. Ion exchange reactions slow radionuclide migration and allow more time for radioactive decay and dispersion. For some radionuclides, solubility alone may limit concentrations to less than the maximum permissible now considered acceptable by the Federal Government. The effectiveness of the geochemical barrier is ultimately related to the repository site characteristics. Theory alone tells us that geochemical controls will be most efficient in an environment that provides for maximum ion exchange and the precipitation of insoluble compounds. In site selection, consideration should be given to rock barriers with high ion exchange capacity that might also act as semi-permeable membranes. Also important in evaluating the site's potential for effective geochemical controls are the oxidation potentials, pH and salinity of the groundwater

  12. Radionuclides in terrestrial ecosystems

    International Nuclear Information System (INIS)

    Howard, B.J.; Kennedy, V.H.; Nelson, A.

    1983-06-01

    A bibliographical database has been developed to provide quick access to research and background literature in the field of radioecology. This is a development of an earlier database described by Nelson (Bocock 1981). ITE's particular fields of interest have led to a subject bias in the bibliography towards studies in Cumbria, especially those concerned with radionuclides originating from the reprocessing plant at Sellafield, and towards ecological research studies that are complementary to radionuclide studies. Other subjects covered, include the chemistry of radionuclides, budgets and transfers within ecosystems and techniques for the analysis of environmental samples. ITE's research objectives have led to the establishment of a specialized database which is intended to complement rather than compete with the large international databases made available by suppliers such as IRS-DIALTECH or DIALOG. Currently the database holds about 1900 references which are stored on a 2 1/2 megabyte hard disk on a Digital PDP11/34 computer operating under a time shared system. The references follow a standard format. (author)

  13. Radionuclides in marine organisms

    International Nuclear Information System (INIS)

    Honda, Teruyuki

    2001-01-01

    The concentration and accumulation of radionuclides in marine organisms were explained in this paper. Secular change of the radioactivity concentration of 137 Cs in seaweed in coastal area of Japan showed more than 5Bq/kg-fresh in the first half of 1960, but decreased less than 1 Bq/kg-fresh after then and attained to less than 0.1 Bq/kg-fresh in 1990s. However, the value increased a while in 1986, which indicated the effect of Chernobyl accident. The accident increased 137 Cs of shellfish near Japan. The concentration of 239+240 Pu was the lowest value in muscles of fish, but increased from 1.7 to 42.3 mBq/kg wet wt in seaweed in 1999. 99 Tc concentration of seaweed showed from 100 to 1000 times as much as that of seawater. Radionuclides in the Irish Sea are originated from Sellafield reprocessing plant. The concentration factors of macro-algae and surface water fish (IAEA,1985) were shown. Analytical results of U in 61 kinds of marine organs showed that the concentration was different in the part of organ. The higher concentration of U was observed in hard tissue of fish. The concentration factor was different between chemical substances with the same radionuclides. (S.Y.)

  14. Proficiency testing for radionuclides

    International Nuclear Information System (INIS)

    Faanhof, A.; Kotze, O.; Louw, I.

    2010-01-01

    Proficiency testing in general is only useful when it suites a certain purpose. With regards to radionuclides basically three fields of interest can be identified: (I)Foodstuffs-Introduced in the early 1960's to monitor the fall-out of nuclear tests and eventually the pathway to foodstuffs fit for human consumption. The demand for analysis increased substantially after the Chernobyl accident. (II) Natural radioactivity-Associated with mining and mineral processing of uranium and thorium baring mineral resources throughout the world where the radionuclides from the natural uranium and thorium decay series are found to pose concern for professional and public exposure. (III) Artificial radioactivity-This category covers mostly the long-lived nuclides generated by nuclear fission of the fuel used in nuclear power plants, research reactors and nuclear bomb tests. All three categories require a specific approach for laboratories to test their ability to analyze specific radio nuclides of interest in a variety of matrices. In this lecture I will give a compiled overview of the required radioanalytical skills, analysis sensitivity needed and radionuclides of interest, with more specific emphasis on QAQC of water sources and the recommended monitoring approach. And provide information on available reference materials and organizations/institutes that provide regular exercises for participating laboratories. I will also briefly communicate on the advantages and disadvantages of ISO/IEC 17025 accreditation for test laboratories, which is these days a prerequisite in national and international trade especially where foodstuffs and mineral products are concerned.

  15. Energy efficient neural stimulation: coupling circuit design and membrane biophysics.

    Science.gov (United States)

    Foutz, Thomas J; Ackermann, D Michael; Kilgore, Kevin L; McIntyre, Cameron C

    2012-01-01

    The delivery of therapeutic levels of electrical current to neural tissue is a well-established treatment for numerous indications such as Parkinson's disease and chronic pain. While the neuromodulation medical device industry has experienced steady clinical growth over the last two decades, much of the core technology underlying implanted pulse generators remain unchanged. In this study we propose some new methods for achieving increased energy-efficiency during neural stimulation. The first method exploits the biophysical features of excitable tissue through the use of a centered-triangular stimulation waveform. Neural activation with this waveform is achieved with a statistically significant reduction in energy compared to traditional rectangular waveforms. The second method demonstrates energy savings that could be achieved by advanced circuitry design. We show that the traditional practice of using a fixed compliance voltage for constant-current stimulation results in substantial energy loss. A portion of this energy can be recuperated by adjusting the compliance voltage to real-time requirements. Lastly, we demonstrate the potential impact of axon fiber diameter on defining the energy-optimal pulse-width for stimulation. When designing implantable pulse generators for energy efficiency, we propose that the future combination of a variable compliance system, a centered-triangular stimulus waveform, and an axon diameter specific stimulation pulse-width has great potential to reduce energy consumption and prolong battery life in neuromodulation devices.

  16. Energy efficient neural stimulation: coupling circuit design and membrane biophysics.

    Directory of Open Access Journals (Sweden)

    Thomas J Foutz

    Full Text Available The delivery of therapeutic levels of electrical current to neural tissue is a well-established treatment for numerous indications such as Parkinson's disease and chronic pain. While the neuromodulation medical device industry has experienced steady clinical growth over the last two decades, much of the core technology underlying implanted pulse generators remain unchanged. In this study we propose some new methods for achieving increased energy-efficiency during neural stimulation. The first method exploits the biophysical features of excitable tissue through the use of a centered-triangular stimulation waveform. Neural activation with this waveform is achieved with a statistically significant reduction in energy compared to traditional rectangular waveforms. The second method demonstrates energy savings that could be achieved by advanced circuitry design. We show that the traditional practice of using a fixed compliance voltage for constant-current stimulation results in substantial energy loss. A portion of this energy can be recuperated by adjusting the compliance voltage to real-time requirements. Lastly, we demonstrate the potential impact of axon fiber diameter on defining the energy-optimal pulse-width for stimulation. When designing implantable pulse generators for energy efficiency, we propose that the future combination of a variable compliance system, a centered-triangular stimulus waveform, and an axon diameter specific stimulation pulse-width has great potential to reduce energy consumption and prolong battery life in neuromodulation devices.

  17. Application of the linear-quadratic model with incomplete repair to radionuclide directed therapy

    International Nuclear Information System (INIS)

    Millar, W.T.; Glasgow Univ.

    1991-01-01

    The LQ model has now been extended to include a general time varying dose rate profile, and the equations can be readily evaluated if an exponential radiation damage repair process is assumed. These equations are applicable to radionuclide directed therapy, including brachytherapy. Kinetic uptake data obtained during radionuclide directed therapy may therefore be used to determine the radiobiological dosimetry of the target and non-target tissues. Also, preliminary tracer studies may be used to pre-plan the radionuclide directed therapy, provided that tracer and therapeutic amounts of the radionuclide carrier are identically processed by the tissues. It is also shown that continuous radionuclide therapy will induce less damage in late-responding tissues than 2 Gy/fraction external beam therapy if the ratio of the maximum dose rate and the sublethal damage repair half-life in the tissue is less than 1.0 Gy. Similar inequalities may be derived for β-particle radionuclide directed therapy. (author)

  18. Biophysical models of larval dispersal in the Benguela Current ...

    African Journals Online (AJOL)

    We synthesise and update results from the suite of biophysical, larval-dispersal models developed in the Benguela Current ecosystem. Biophysical models of larval dispersal use outputs of physical hydrodynamic models as inputs to individual-based models in which biological processes acting during the larval life are ...

  19. Biophysics: for HTS hit validation, chemical lead optimization, and beyond.

    Science.gov (United States)

    Genick, Christine C; Wright, S Kirk

    2017-09-01

    There are many challenges to the drug discovery process, including the complexity of the target, its interactions, and how these factors play a role in causing the disease. Traditionally, biophysics has been used for hit validation and chemical lead optimization. With its increased throughput and sensitivity, biophysics is now being applied earlier in this process to empower target characterization and hit finding. Areas covered: In this article, the authors provide an overview of how biophysics can be utilized to assess the quality of the reagents used in screening assays, to validate potential tool compounds, to test the integrity of screening assays, and to create follow-up strategies for compound characterization. They also briefly discuss the utilization of different biophysical methods in hit validation to help avoid the resource consuming pitfalls caused by the lack of hit overlap between biophysical methods. Expert opinion: The use of biophysics early on in the drug discovery process has proven crucial to identifying and characterizing targets of complex nature. It also has enabled the identification and classification of small molecules which interact in an allosteric or covalent manner with the target. By applying biophysics in this manner and at the early stages of this process, the chances of finding chemical leads with novel mechanisms of action are increased. In the future, focused screens with biophysics as a primary readout will become increasingly common.

  20. Biophysics of NASA radiation quality factors

    International Nuclear Information System (INIS)

    Cucinotta, Francis A.

    2015-01-01

    NASA has implemented new radiation quality factors (QFs) for projecting cancer risks from space radiation exposures to astronauts. The NASA QFs are based on particle track structure concepts with parameters derived from available radiobiology data, and NASA introduces distinct QFs for solid cancer and leukaemia risk estimates. The NASA model was reviewed by the US National Research Council and approved for use by NASA for risk assessment for International Space Station missions and trade studies of future exploration missions to Mars and other destinations. A key feature of the NASA QFs is to represent the uncertainty in the QF assessments and evaluate the importance of the QF uncertainty to overall uncertainties in cancer risk projections. In this article, the biophysical basis for the probability distribution functions representing QF uncertainties was reviewed, and approaches needed to reduce uncertainties were discussed. (author)

  1. Biophysics of NASA radiation quality factors.

    Science.gov (United States)

    Cucinotta, Francis A

    2015-09-01

    NASA has implemented new radiation quality factors (QFs) for projecting cancer risks from space radiation exposures to astronauts. The NASA QFs are based on particle track structure concepts with parameters derived from available radiobiology data, and NASA introduces distinct QFs for solid cancer and leukaemia risk estimates. The NASA model was reviewed by the US National Research Council and approved for use by NASA for risk assessment for International Space Station missions and trade studies of future exploration missions to Mars and other destinations. A key feature of the NASA QFs is to represent the uncertainty in the QF assessments and evaluate the importance of the QF uncertainty to overall uncertainties in cancer risk projections. In this article, the biophysical basis for the probability distribution functions representing QF uncertainties was reviewed, and approaches needed to reduce uncertainties were discussed. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  2. Low temperature experiments in radiation biophysics

    International Nuclear Information System (INIS)

    Moan, J.

    1977-01-01

    The reasons for performing experiments in radiation biophysics at low temperatures, whereby electron spectra may be studied, are explained. The phenomenon of phosphorescence spectra observed in frozen aqueous solutions of tryptophan and adenosine is also described. Free radicals play an important part in biological radiation effects and may be studied by ESR spectroscopy. An ESR spectrum of T 1 bacteriophages irradiated dry at 130K is illustrated and discussed. Hydrogen atoms, which give lines on the spectrum, are believed to be those radiation products causing most biological damage in a dry system. Low temperature experiments are of great help in explaining the significance of direct and indirect effects. This is illustrated for the case of trypsin. (JIW)

  3. Microwave Tissue Ablation: Biophysics, Technology and Applications

    Science.gov (United States)

    2010-01-01

    Microwave ablation is an emerging treatment option for many cancers, cardiac arrhythmias and other medical conditions. During treatment, microwaves are applied directly to tissues to produce rapid temperature elevations sufficient to produce immediate coagulative necrosis. The engineering design criteria for each application differ, with individual consideration for factors such as desired ablation zone size, treatment duration, and procedural invasiveness. Recent technological developments in applicator cooling, power control and system optimization for specific applications promise to increase the utilization of microwave ablation in the future. This article will review the basic biophysics of microwave tissue heating, provide an overview of the design and operation of current equipment, and outline areas for future research for microwave ablation. PMID:21175404

  4. Radionuclide therapy: regional and systemic routes of administration

    International Nuclear Information System (INIS)

    Shapiro, B.

    1991-01-01

    The optimal sequencing and integration of radiopharmaceutical therapy with respect to the multiple and competing therapeutic modalities is examined. It is estimated that the central goal of therapeutic nuclear medicine is to increase radiopharmaceutical delivery to tumour targets while sparing sensitive normal tissues. Among the factors to be considered in the choice of therapeutic radionuclides are: the decay mode, gamma-ray yield, half-lives and chemical reactivity. Several routes of administration are discussed and a number of manipulations which may be used to further improve radioparmaceutical delivery are outlined. The difficulty to perform accurate radiation dosimetry is also briefly examined. 14 refs., 1 tab

  5. CREB Overexpression Ameliorates Age-related Behavioral and Biophysical Deficits

    Science.gov (United States)

    Yu, Xiao-Wen

    overexpressing CREB had increased excitability. This indicates that overexpression of CREB was sufficient to rescue both the cognitive deficits, and the biophysical dysfunction normally seen in aged animals. Together, the results from this thesis identify CREB as a new mechanism underlying age-related cognitive deficits. This not only furthers our understanding of how cognitive processes change with age, but also suggests that increasing activity of CREB or its downstream transcription targets may be a novel therapeutic for the treatment of age-related cognitive decline.

  6. Biophysical mechanisms complementing "classical" cell biology.

    Science.gov (United States)

    Funk, Richard H W

    2018-01-01

    This overview addresses phenomena in cell- and molecular biology which are puzzling by their fast and highly coordinated way of organization. Generally, it appears that informative processes probably involved are more on the biophysical than on the classical biochemical side. The coordination problem is explained within the first part of the review by the topic of endogenous electrical phenomena. These are found e.g. in fast tissue organization and reorganization processes like development, wound healing and regeneration. Here, coupling into classical biochemical signaling and reactions can be shown by modern microscopy, electronics and bioinformatics. Further, one can follow the triggered reactions seamlessly via molecular biology till into genetics. Direct observation of intracellular electric processes is very difficult because of e.g. shielding through the cell membrane and damping by other structures. Therefore, we have to rely on photonic and photon - phonon coupling phenomena like molecular vibrations, which are addressed within the second part. Molecules normally possess different charge moieties and thus small electromagnetic (EMF) patterns arise during molecular vibration. These patterns can now be measured best within the optical part of the spectrum - much less in the lower terahertz till kHz and lower Hz part (third part of this review). Finally, EMFs facilitate quantum informative processes in coherent domains of molecular, charge and electron spin motion. This helps to coordinate such manifold and intertwined processes going on within cells, tissues and organs (part 4). Because the phenomena described in part 3 and 4 of the review still await really hard proofs we need concerted efforts and a combination of biophysics, molecular biology and informatics to unravel the described mysteries in "physics of life".

  7. Development of medical application methods using radiation. Radionuclide therapy

    International Nuclear Information System (INIS)

    Choi, Chang Woon; Lim, S. M.; Kim, E.H.; Woo, K. S.; Chung, W. S.; Lim, S. J.; Choi, T. H.; Hong, S. W.; Chung, H. Y.; No, W. C.; Oh, B. H.; Hong, H. J.

    1999-04-01

    In this project, we studied following subjects: 1. development of monoclonal antibodies and radiopharmaceuticals 2. clinical applications of radionuclide therapy 3. radioimmunoguided surgery 4. prevention of restenosis with intracoronary radiation. The results can be applied for the following objectives: 1) radionuclide therapy will be applied in clinical practice to treat the cancer patients or other diseases in multi-center trial. 2) The newly developed monoclonal antibodies and biomolecules can be used in biology, chemistry or other basic life science research. 3) The new methods for the analysis of therapeutic effects, such as dosimetry, and quantitative analysis methods of radioactivity, can be applied in basic research, such as radiation oncology and radiation biology

  8. Development of medical application methods using radiation. Radionuclide therapy

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chang Woon; Lim, S. M.; Kim, E.H.; Woo, K. S.; Chung, W. S.; Lim, S. J.; Choi, T. H.; Hong, S. W.; Chung, H. Y.; No, W. C. [Korea Atomic Energy Research Institute. Korea Cancer Center Hospital, Seoul, (Korea, Republic of); Oh, B. H. [Seoul National University. Hospital, Seoul (Korea, Republic of); Hong, H. J. [Antibody Engineering Research Unit, Taejon (Korea, Republic of)

    1999-04-01

    In this project, we studied following subjects: 1. development of monoclonal antibodies and radiopharmaceuticals 2. clinical applications of radionuclide therapy 3. radioimmunoguided surgery 4. prevention of restenosis with intracoronary radiation. The results can be applied for the following objectives: (1) radionuclide therapy will be applied in clinical practice to treat the cancer patients or other diseases in multi-center trial. (2) The newly developed monoclonal antibodies and biomolecules can be used in biology, chemistry or other basic life science research. (3) The new methods for the analysis of therapeutic effects, such as dosimetry, and quantitative analysis methods of radioactivity, can be applied in basic research, such as radiation oncology and radiation biology.

  9. Initial experience with software system JODNEW for evaluation biophysical characteristics related to treatment of carcinoma of thyroid gland by 131I

    International Nuclear Information System (INIS)

    Hermanska, J.; Zimak, J.; Vosminkova, K.; Nemec, J.; Blazek, T.; Jirsa, L.; Karny, M.

    1998-01-01

    Our research tries to exploit sophisticated methods for a balancing of positive and negative consequences of radionuclide applications. We have tailored Bayesian data processing in order to support decision making during treatment of thyroid diseases with help of 131 I. After successful experimental phase we have implemented them. This novel in-house developed software system JODNEW i now tested. It aim at: (1) increasing quality of raw biophysical data exploited in diagnostics and therapy of thyroid diseases; (2) estimating cumulated activity so that MIRD methodology can be well used; (3) decreasing working load on staff. JODNEW is an extensive data-base system co-operating with advanced estimation algorithms coded in C++. The Bayesian methodology adopted allows us to exploit expert knowledge, models of observed processes as well as measured data in a consistent way. This is important in the considered case when the number of measurements is quite limited and influence of biological and physical variations is high. Moreover, all estimates are qualified by the remaining uncertainty. During diagnostics> The (functioning) volume of thyroid gland and body mass are measured. A diagnostic amount of 131 I is administered. Three whole body measurements of elimination rate by urine (excretions) are made within 2 days after administration. The accumulated activities above thyroid gland and other lesions are registered within several days. Evaluation and measurements during therapy are: The accumulation ability is evaluated using diagnostic data. Consequences of 131 I administration are judged, then, the therapeutic activity is selected and administered. The accumulation dynamics is supervised and reaching radio-hygienic limits influencing patient regime is predicted. The common features of these steps are: (1) Individual measurements are corrupted by a high and varying uncertainty; (2) The number of measurements is limited; (3) A significant expert experience is available

  10. Preparation of Radiopharmaceuticals Labeled with Metal Radionuclides. Final Report

    International Nuclear Information System (INIS)

    Welch, M.J.

    2012-01-01

    retention of the tissue and the significantly greater retention amounting in hypoxic tissue. This hypothesis was confirmed in a series of animal studies. Cu-64 can be used both as an imaging radionuclide and a therapeutic radionuclide. The therapeutic efficacy of Cu-64 ATSM was proven in hamsters bearing the CW39 human colorectal tumors. The administration of Cu-64 ATSM significantly increased the survival time of tumor-bearing animals with no acute toxicity. This copper agent therefore shows promise for radiotherapy. The flow tracer Cu-64 PTSM also demonstrates therapeutic potential by inhibiting cancer cells implanted in animal models. Again, this inhibition occurred at doses which showed no sign of toxicity to the animals. Cu-ATSM was translated to humans, under other support a series of tumors were investigated; these included head and neck cancer, non-small cell lung cancer, cervical cancer and renal cancer. Another radionuclide that was investigated was titanium 45. This radionuclide was successfully produced by radiation of a scandium foil with 15 MeV protons. The titanium 45 was processed and separated from residual scandium by high exchange chomotrophy. Titanium titanocene has been utilized as a therapeutic agent; this compound was prepared and studied in vitro and in vivo. Another project was the preparation of cyclodextrin dimers as a new pre-targeting approach for tumor uptake. Beta-cyclodextradin and two other dimers were synthesized. These dimers were studied for the in vivo application. Work continued on the application of the radionuclide already discussed. Technetium 94m, a positron emitting radionuclide of the widely used 99m Tc nuclide was also prepared. This allows the quantification of the uptake of technetium radiopharmaceuticals. In collaboration with Professor David Piwnica-Worms, technetium 94m, sestamibi was studied in animal models and in a limited number of human subjects.

  11. Chapter 2. Radionuclides in the biosphere

    International Nuclear Information System (INIS)

    Toelgyessy, J.; Harangozo, M.

    2000-01-01

    This is a chapter of textbook of radioecology for university students. In this chapter authors deal with role of radionuclides in the biosphere. Chapter consists of next parts: (1) Natural radionuclides in biosphere; (2) Man-made radionuclides in the biosphere; (3) Ecologically important radionuclides; (4) Natural background; (5) Radiotoxicity and (6) Paths of transfer of radionuclides from the source to human

  12. Radionuclide diagnosis of emergency states

    International Nuclear Information System (INIS)

    Ishmukhametov, A.I.

    1985-01-01

    Solution of emergency state radionuclide diagnostics from the technical point of view is provided by the application of the mobile quick-operating equipment in combination with computers, by the use of radionuclides with acceptable for emergency medicine characteristics and by development of radionuclide investigation data propcessing express-method. Medical developments include the study of acute disease and injury radioisotope semiotics, different indication diagnostic value determining, comparison of the results, obtained during radionuclide investigation, with clinicolaboratory and instrumental data, separation of methodical complex series

  13. History of medical radionuclide production.

    Science.gov (United States)

    Ice, R D

    1995-11-01

    Radionuclide production for medical use originally was incidental to isotope discoveries by physicists and chemists. Once the available radionuclides were identified they were evaluated for potential medical use. Hevesy first used 32P in 1935 to study phosphorous metabolism in rats. Since that time, the development of cyclotrons, linear accelerators, and nuclear reactors have produced hundreds of radionuclides for potential medical use. The history of medical radionuclide production represents an evolutionary, interdisciplinary development of applied nuclear technology. Today the technology is represented by a mature industry and provides medical benefits to millions of patients annually.

  14. EBS Radionuclide Transport Abstraction

    Energy Technology Data Exchange (ETDEWEB)

    J.D. Schreiber

    2005-08-25

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport

  15. EBS Radionuclide Transport Abstraction

    International Nuclear Information System (INIS)

    J.D. Schreiber

    2005-01-01

    The purpose of this report is to develop and analyze the engineered barrier system (EBS) radionuclide transport abstraction model, consistent with Level I and Level II model validation, as identified in ''Technical Work Plan for: Near-Field Environment and Transport: Engineered Barrier System: Radionuclide Transport Abstraction Model Report Integration'' (BSC 2005 [DIRS 173617]). The EBS radionuclide transport abstraction (or EBS RT Abstraction) is the conceptual model used in the total system performance assessment for the license application (TSPA-LA) to determine the rate of radionuclide releases from the EBS to the unsaturated zone (UZ). The EBS RT Abstraction conceptual model consists of two main components: a flow model and a transport model. Both models are developed mathematically from first principles in order to show explicitly what assumptions, simplifications, and approximations are incorporated into the models used in the TSPA-LA. The flow model defines the pathways for water flow in the EBS and specifies how the flow rate is computed in each pathway. Input to this model includes the seepage flux into a drift. The seepage flux is potentially split by the drip shield, with some (or all) of the flux being diverted by the drip shield and some passing through breaches in the drip shield that might result from corrosion or seismic damage. The flux through drip shield breaches is potentially split by the waste package, with some (or all) of the flux being diverted by the waste package and some passing through waste package breaches that might result from corrosion or seismic damage. Neither the drip shield nor the waste package survives an igneous intrusion, so the flux splitting submodel is not used in the igneous scenario class. The flow model is validated in an independent model validation technical review. The drip shield and waste package flux splitting algorithms are developed and validated using experimental data. The transport model considers

  16. Macrocyclic complexes of radionuclides in nuclear medicine

    International Nuclear Information System (INIS)

    Majkowska, A.; Bilewicz, A.

    2008-01-01

    The use of radiometal-labeled small complexes and biomolecules as diagnostic and therapeutic agents is a relatively new area of medical research. Radiopharmaceuticals are radiolabeled molecules designed to deliver ionizing radiation doses to specific disease sites. Between the targeting biomolecule and a radionuclide a bifunctional ligand is inserted, one end of which is covalently attached to the targeting molecule either directly or through a linker whereas the other strongly coordinates a metallic radionuclide. Selection of a bifunctional ligand is largely determined by the nature and oxidation state of a metal ion. The metal chelate can significantly affect the tumor uptake and biodistribution of radiopharmaceuticals based on small biomolecules. This is because in many cases the metal chelate contributes greatly to the overall size and lipophilicity of the radiopharmaceutical. Therefore, the design and selection of the ligand is very important for the development of a clinically useful therapeutic agent. The requirement for high thermodynamic and kinetic stability of the metal complex is often achieved through the use of macrocyclic ligands with a functionalized arm for covalent bonding to the biomolecule. In this review synthesis of bifunctional macrocyclic ligands and properties of radionuclide macrocyclic complexes used in nuclear medicine are presented. We describe results in two areas: substituted macrocyclic aza ligands for chelation of hard metal cations, and macrocycles containing sulphur for complexation of soft metal cations. Special attention was paid to stability of the complexes as well as to their lipophilicity, which affect biological properties of the formed radiopharmaceuticals. We also include a forecast of the near-term opportunities that are likely to determine practice in the next few years. (authors)

  17. Osteopetrosis: Radiological & Radionuclide Imaging

    International Nuclear Information System (INIS)

    Sit, Cherry; Agrawal, Kanhaiyalal; Fogelman, Ignac; Gnanasegaran, Gopinath

    2015-01-01

    Osteopetrosis is a rare inherited bone disease where bones harden and become abnormally dense. While the diagnosis is clinical, it also greatly relies on appearance of the skeleton radiographically. X-ray, radionuclide bone scintigraphy and magnetic resonance imaging have been reported to identify characteristics of osteopetrosis. We present an interesting case of a 59-year-old man with a history of bilateral hip fractures. He underwent 99m Tc-methylene diphosphonate whole body scan supplemented with single-photon emission computed tomography/computed tomography of spine, which showed increased uptake in the humeri, tibiae and femora, which were in keeping with osteopetrosis

  18. Modifying radionuclide effects

    International Nuclear Information System (INIS)

    Sasser, L.B.

    1983-01-01

    This project involves a study of the relationship of physiological and environmental factors to the metabolism and effects of radionuclides. We have studied placental transfer and suckling as pathways of americium entry into the newborn or juvenile rat. Rats were injected intravenously with 5 μCi of 241 Am while nulliparous (30 days prior to mating), pregnant (day 19 of gestation), or lactating (1 day after parturition), and subsequent litters were killed to determine 241 Am retention. A deficit in reproductive performance was observed in the group injected before mating, as evidenced by reduced number and weight of offspring

  19. Radionuclides in the sea

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1971-07-01

    Water covers a little more than two-thirds of the earth's surface. What is thrown into the sea from a ship may be washed up on a shore thousands of miles away; wastes discharged into the seas or into rivers flowing into them can affect marine life and possibly also the health of man. The study, prevention and control of pollution of the seas and oceans by radionuclides introduced as by-products of man's use of nuclear energy is thus of global interest. (author)

  20. Sherlock Holmes for radionuclides

    International Nuclear Information System (INIS)

    Schmitzer, C.

    2002-01-01

    At the end of 2001 ARC Seibersdorf research has taken the management of the first worldwide certified laboratory to control the realization of the international Comprehensive Nuclear Test Ban Treaty (CTBT). Altogether there will be 16 CTBT certified laboratories worldwide; therefore a global network of radionuclides measurements stations and test laboratories as well as seismic, radiation and hydroacustic measurements stations is necessary . In the future air samples will be taken from these stations and analyzed in one of these certified laboratories, when appears the suspicion that an atomic test was carried out. (nevyjel)

  1. Interplay of mycolic acids, antimycobacterial compounds and pulmonary surfactant membrane: a biophysical approach to disease.

    Science.gov (United States)

    Pinheiro, Marina; Giner-Casares, Juan J; Lúcio, Marlene; Caio, João M; Moiteiro, Cristina; Lima, José L F C; Reis, Salette; Camacho, Luis

    2013-02-01

    This work focuses on the interaction of mycolic acids (MAs) and two antimycobacterial compounds (Rifabutin and N'-acetyl-Rifabutin) at the pulmonary membrane level to convey a biophysical perspective of their role in disease. For this purpose, accurate biophysical techniques (Langmuir isotherms, Brewster angle microscopy, and polarization-modulation infrared reflection spectroscopy) and lipid model systems were used to mimic biomembranes: MAs mimic bacterial lipids of the Mycobacterium tuberculosis (MTb) membrane, whereas Curosurf® was used as the human pulmonary surfactant (PS) membrane model. The results obtained show that high quantities of MAs are responsible for significant changes on PS biophysical properties. At the dynamic inspiratory surface tension, high amounts of MAs decrease the order of the lipid monolayer, which appears to be a concentration dependent effect. These results suggest that the amount of MAs might play a critical role in the initial access of the bacteria to their targets. Both molecules also interact with the PS monolayer at the dynamic inspiratory surface. However, in the presence of higher amounts of MAs, both compounds improve the phospholipid packing and, therefore, the order of the lipid surfactant monolayer. In summary, this work discloses the putative protective effects of antimycobacterial compounds against the MAs induced biophysical impairment of PS lipid monolayers. These protective effects are most of the times overlooked, but can constitute an additional therapeutic value in the treatment of pulmonary tuberculosis (Tb) and may provide significant insights for the design of new and more efficient anti-Tb drugs based on their behavior as membrane ordering agents. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Radionuclide Therapy. Chapter 19

    Energy Technology Data Exchange (ETDEWEB)

    Flux, G.; Du, Yong [Royal Marsden Hospital and Institute of Cancer Research, Surrey (United Kingdom)

    2014-12-15

    Cancer has been treated with radiopharmaceuticals since the 1940s. The radionuclides originally used, including 131I and 32P, are still in use. The role of the physicist in radionuclide therapy encompasses radiation protection, imaging and dosimetry. Radiation protection is of particular importance given the high activities of the unsealed sources that are often administered, and must take into account medical staff, comforters and carers, and, as patients are discharged while still retaining activity, members of the public. Regulations concerning acceptable levels of exposure vary from country to country. If the administered radiopharmaceutical is a γ emitter, then imaging can be performed which may be either qualitative or quantitative. While a regular system of quality control must be in place to prevent misinterpretation of image data, qualitative imaging does not usually rely on the image corrections necessary to determine the absolute levels of activity that are localized in the patient. Accurate quantitative imaging is dependent on these corrections and can permit the distribution of absorbed doses delivered to the patient to be determined with sufficient accuracy to be clinically beneficial.

  3. Intervention procedures for radionuclides

    International Nuclear Information System (INIS)

    Adelstein, S.J.

    1991-01-01

    As in the case of smoking and lung cancer, for large radionuclide releases, an ounce of prevention is worth a pound of cure. On the other hand, we feel compelled to do something sensible after an accident even if the principal benefit of intervention may be to comfort the population at risk. Of course, for populations near the site of an accident, evacuation should be considered, but it is unreasonable to apply this measure to distant populations, e.g., large segments of the European community could not be moved about as we observe the shifting of a radioactive cloud in response to changing winds. If the radionuclides are delivered as particulates, bringing people indoors and employing primitive air filters can temporarily reduce exposures, but these stratagems are not very effective against gaseous or volatile elements. What, then, can be done for populations downwind of a radioactive release whose air, water, and/or food supply are, or are about to become contaminated? 5 refs

  4. New aspects of radionuclide therapy of bone and joint diseases

    International Nuclear Information System (INIS)

    Fischer, M.

    2001-01-01

    Whereas in developing countries P-32 is widely used for radionuclide therapy of painful bone metastases, in Europe three radionuclides or radiopharmaceutical agents are available for pain palliation: Sr-89, Sm-153-EDTMP, and Re-186-HEDP. Radionuclide therapy for pain palliation is indicated for bone pain due to metastatic malignancy that has involved multiple skeletal sites and has evoked an osteoblastic response on bone scintigraphy. Response rates of about 70-80% in patients with breast or prostate cancer is reported in the literature, less in metastatic lesions of other primary malignancies. Sm-153-EDTMP may also be used for curative treatment of primary bone tumours or their metastases. Radiosynovectomy as therapeutic procedure or rheumatoid arthritis, other inflammatory joint diseases, persistent synovial perfusion, and other joint diseases is widely used. Using Y-90 for the knee joint, Re-186 for middle sized joints, and Er-169 for small joints an improvement of symptoms may be observed in about 70-80%. (author)

  5. Treatment of metastasis localizations by intratumoral injection of radionuclide microsphere

    International Nuclear Information System (INIS)

    Tuo Peiyu; Pang Yan; Zhu Dianqing; Chang Keli; Zhu Yanjia

    2001-01-01

    Objective: To evaluate the therapeutic effects of radionuclide-labeled microsphere by intratumoral injection into 18 patients with superficial metastasis tumor for treatment. Methods: 18 patients with superficial metastasis were treated with radionuclide-labeled microsphere ( 90 Y-GTMS and 32 P-GTMS) by multi-point intratumoral injection. Each injection dose was 11.1-18.5 MBq/g (tumor). Results: 1 patient was relieved completely, 9 were relieved partly, 5 were improved and 3 kept stable. The total rate of relief and virtual value were 55.6% and 83.3% respectively. Conclusion: Topical treatment by using radionuclide may help diminish the tumor, control its progress and ease the symptoms. Thus it can be used as a supplement of routine treatment of tumors and it should do some work in therapy of malignant tumors in late stages

  6. Some parameters of radionuclide kinetics

    International Nuclear Information System (INIS)

    Prokof'ev, O.N.; Smirnov, V.A.; Belen'kij, E.I.

    1978-01-01

    Numerical values of the rates of radionuclide absorption into, and elimination from, bovine organs were determined. Kinetic rate constants of radionuclides such as 89 Sr, 99 Mo, 131 I, 132 Tl, and 140 Be were calculated. The calculations were done for muscle, liver, and kidney

  7. Radionuclide - Soil Organic Matter Interactions

    DEFF Research Database (Denmark)

    Carlsen, Lars

    1985-01-01

    Interactions between soil organic matter, i.e. humic and fulvic acids, and radionuclides of primary interest to shallow land burial of low activity solid waste have been reviewed and to some extent studied experimentally. The radionuclides considered in the present study comprise cesium, strontium...

  8. Chapter 13. Radionuclides in medicine

    International Nuclear Information System (INIS)

    Toelgyessy, J.; Harangozo, M.

    2000-01-01

    This is a chapter of textbook of radioecology for university students. In this chapter authors deal with problems connected with using of radionuclides in medicine. Methods of treatment with using of radionuclides are reviewed. Chapter consists of next parts: (1) Remotion of thyroid gland; (2) Treatment of cerebrally tumour in nuclear reactor; (3) Artificial heart

  9. Biophysically realistic minimal model of dopamine neuron

    Science.gov (United States)

    Oprisan, Sorinel

    2008-03-01

    We proposed and studied a new biophysically relevant computational model of dopaminergic neurons. Midbrain dopamine neurons are involved in motivation and the control of movement, and have been implicated in various pathologies such as Parkinson's disease, schizophrenia, and drug abuse. The model we developed is a single-compartment Hodgkin-Huxley (HH)-type parallel conductance membrane model. The model captures the essential mechanisms underlying the slow oscillatory potentials and plateau potential oscillations. The main currents involved are: 1) a voltage-dependent fast calcium current, 2) a small conductance potassium current that is modulated by the cytosolic concentration of calcium, and 3) a slow voltage-activated potassium current. We developed multidimensional bifurcation diagrams and extracted the effective domains of sustained oscillations. The model includes a calcium balance due to the fundamental importance of calcium influx as proved by simultaneous electrophysiological and calcium imaging procedure. Although there are significant evidences to suggest a partially electrogenic calcium pump, all previous models considered only elecrtogenic pumps. We investigated the effect of the electrogenic calcium pump on the bifurcation diagram of the model and compared our findings against the experimental results.

  10. Biophysical and biomathematical adventures in radiobiology

    International Nuclear Information System (INIS)

    Scott, B.R.

    1991-01-01

    Highlights of my biophysical and biomathematical adventures in radiobiology is presented. Early adventures involved developing ''state-vector models'' for specific harmful effects (cell killing, life shortening) of exposure to radiation. More recent adventures led to developing ''hazard-function models'' for predicting biological effects (e.g., cell killing, mutations, tumor induction) of combined exposure to different toxicants. Hazard-function models were also developed for predicting harm to man from exposure to large radiation doses. Major conclusions derived from the modeling adventures are as follows: (1) synergistic effects of different genotoxic agents should not occur at low doses; (2) for exposure of the lung or bone marrow to large doses of photon radiation, low rates of exposure should be better tolerated than high rates; and (3) for some types of radiation (e.g., alpha particles and fission neutrons), moderate doses delivered at a low rate may be more harmful than the same dose given at a high rate. 53 refs., 7 figs

  11. Review of FEWS NET Biophysical Monitoring Requirements

    Science.gov (United States)

    Ross, K. W.; Brown, Molly E.; Verdin, J.; Underwood, L. W.

    2009-01-01

    The Famine Early Warning System Network (FEWS NET) provides monitoring and early warning support to decision makers responsible for responding to famine and food insecurity. FEWS NET transforms satellite remote sensing data into rainfall and vegetation information that can be used by these decision makers. The National Aeronautics and Space Administration has recently funded activities to enhance remote sensing inputs to FEWS NET. To elicit Earth observation requirements, a professional review questionnaire was disseminated to FEWS NET expert end-users: it focused upon operational requirements to determine additional useful remote sensing data and; subsequently, beneficial FEWS NET biophysical supplementary inputs. The review was completed by over 40 experts from around the world, enabling a robust set of professional perspectives to be gathered and analyzed rapidly. Reviewers were asked to evaluate the relative importance of environmental variables and spatio-temporal requirements for Earth science data products, in particular for rainfall and vegetation products. The results showed that spatio-temporal resolution requirements are complex and need to vary according to place, time, and hazard: that high resolution remote sensing products continue to be in demand, and that rainfall and vegetation products were valued as data that provide actionable food security information.

  12. Contribution to researches in biophysics and biology

    International Nuclear Information System (INIS)

    Luccioni, Catherine

    2000-01-01

    In this accreditation to supervise research, the author indicates its curriculum and scientific works which mainly dealt with the different agents used in chemotherapy. Scientific works addressed anti-carcinogenic pharmacology, applied biophysics, and researches in oncology and radiobiology. Current research projects deal with mechanisms of cellular transformation and the implication of the anti-oxidising metabolism and of nucleotide metabolism in cell radio-sensitivity. Teaching and research supervising activities are also indicated. Several articles are proposed in appendix: Average quality factor and dose equivalent meter based on microdosimetry techniques; Activity of thymidylate synthetase, thymidine kinase and galactokinase in primary and xenografted human colorectal cancers in relation to their chromosomal patterns; Nucleotide metabolism in human gliomas, relation to the chromosomal profile; Pyrimidine nucleotide metabolism in human colon carcinomas: comparison of normal tissues, primary tumors and xenografts; Modifications of the antioxidant metabolism during proliferation and differentiation of colon tumours cell lines; Modulation of the antioxidant enzymes, p21 and p53 expression during proliferation and differentiation of human melanoma cell lines; Purine metabolism in 2 human melanoma cell lines, relation with proliferation and differentiation; Radiation-induced changes in nucleotide metabolism of 2 colon cancer cell lines with different radio-sensitivities

  13. Radionuclide transverse section imager

    International Nuclear Information System (INIS)

    Stoddart, H.F.

    1980-01-01

    A radioisotope scanning apparatus for use in nuclear medicine is described in detail. The apparatus enables the quantification and spatial location of the radioactivity in a body section of a patient to be determined with high sensitivity. It consists of an array of highly focussed collimators arranged such that adjacent collimators move in the same circumferential but opposite radial directions. The explicit movements of the gantry are described in detail and may be controlled by a general purpose computer. The use of highly focussed collimators allows both a reasonable solid angle of acceptance and also high target to background images; additionally, dual radionuclide pharmaceutical studies can be performed simultaneously. It is claimed that the high sensitivity of the system permits the early diagnosis of pathological changes and the images obtained show accurately the location and shape of physiological abnormalities. (UK)

  14. Radioactivity, radionuclides, radiation

    CERN Document Server

    Magill, Joseph

    2005-01-01

    RADIOACTIVITY – RADIONUCLIDES – RADIATION is suitable for a general audience interested in topical environmental and human health radiological issues such as radiation exposure in aircraft, food sterilisation, nuclear medicine, radon gas, radiation dispersion devices ("dirty bombs")… It leads the interested reader through the three Rs of nuclear science, to the forefront of research and developments in the field. The book is also suitable for students and professionals in the related disciplines of nuclear and radiochemistry, health physics, environmental sciences, nuclear and astrophysics. Recent developments in the areas of exotic decay modes (bound beta decay of ‘bare’ or fully ionized nuclei), laser transmutation, nuclear forensics, radiation hormesis and the LNT hypothesis are covered. Atomic mass data for over 3000 nuclides from the most recent (2003) evaluation are included.

  15. Deep sea radionuclides

    International Nuclear Information System (INIS)

    Kanisch, G.; Vobach, M.

    1993-01-01

    Every year since 1979, either in sping or in summer, the fishing research vessel 'Walther Herwig' goes to the North Atlantic disposal areas of solid radioactive wastes, and, for comparative purposes, to other areas, in order to collect water samples, plankton and nekton, and, from the deep sea bed, sediment samples and benthos organisms. In addition to data on the radionuclide contents of various media, information about the plankton, nekton and benthos organisms living in those areas and about their biomasses could be gathered. The investigations are aimed at acquiring scientifically founded knowledge of the uptake of radioactive substances by microorganisms, and their migration from the sea bottom to the areas used by man. (orig.) [de

  16. Radionuclide reporter gene imaging

    International Nuclear Information System (INIS)

    Min, Jung Joon

    2004-01-01

    Recent progress in the development of non-invasive imaging technologies continues to strengthen the role of molecular imaging biological research. These tools have been validated recently in variety of research models, and have been shown to provide continuous quantitative monitoring of the location(s), magnitude, and time-variation of gene expression. This article reviews the principles, characteristics, categories and the use of radionuclide reporter gene imaging technologies as they have been used in imaging cell trafficking, imaging gene therapy, imaging endogenous gene expression and imaging molecular interactions. The studies published to date demonstrate that reporter gene imaging technologies will help to accelerate model validation as well as allow for clinical monitoring of human diseases

  17. Radionuclide reporter gene imaging

    Energy Technology Data Exchange (ETDEWEB)

    Min, Jung Joon [School of Medicine, Chonnam National Univ., Gwangju (Korea, Republic of)

    2004-04-01

    Recent progress in the development of non-invasive imaging technologies continues to strengthen the role of molecular imaging biological research. These tools have been validated recently in variety of research models, and have been shown to provide continuous quantitative monitoring of the location(s), magnitude, and time-variation of gene expression. This article reviews the principles, characteristics, categories and the use of radionuclide reporter gene imaging technologies as they have been used in imaging cell trafficking, imaging gene therapy, imaging endogenous gene expression and imaging molecular interactions. The studies published to date demonstrate that reporter gene imaging technologies will help to accelerate model validation as well as allow for clinical monitoring of human diseases.

  18. Natural radionuclides in groundwaters

    International Nuclear Information System (INIS)

    Laul, J.C.

    1990-01-01

    The U-234 and Th-230 radionuclides are highly retarded by factors of 10 4 to 10 5 in basalt groundwater (Hanford) and briny groundwaters from Texas and geothermal brine from the Salton Sea Geothermal Field (SSGF). In basalt groundwaters (low ionic strength), Ra is highly sorbed, while in brines (high ionic strength), Ra is soluble. This is probably because the sorption sites are saturated with Na + and Cl - ions and RaCl 2 is soluble in brines. Pb-210 is soluble in SSGF brine, probably as a chloride complex. The U-234/Th-230 ratios in basalt groundwaters and brines from Texas and SSGF are nearly unity, indicating that U is in the +4 state, suggesting a reducing environment for these aquifers. 19 refs., 3 figs

  19. Natural radionuclides in groundwaters

    International Nuclear Information System (INIS)

    Laul, J.C.

    1992-01-01

    The 234 U and 230 Th radionuclides are highly retarded by factors of 10 4 to 10 5 in basalt groundwater (Hanford) and briny groundwaters from Texas, and geothermal brine form the Salton Sea Geothermal Field (SSGF). In basalt groundwaters (low ionic strength), Ra is highly sorbed, while in brines (high ionic strength), Ra is soluble. This is probably because the sorption sites are saturated with Na + and Cl - ions, and RaCl 2 is soluble in brines. 210 Pb is soluble in SSGF brine, probably as a chloride complex. The 234 U/ 230 Th ratios in basalt groundwaters and brines from Texas and SSGF are nearly unity, indicating that U is in the +4 state, suggesting a reducing environment for these aquifers. (author) 19 refs.; 3 figs

  20. Therapy with radionuclides

    International Nuclear Information System (INIS)

    Biersack, H.J.; Hotze, A.L.

    1992-01-01

    Radioiodine therapy of benign and malignant thyroid diseases is a well-established procedure in Nuclear Medicine. However, the therapeutic use of radioisotopes in other diseases is relatively unknown among our refering physicians. The therapeutic effects of intraarticular (rheumatoid arthritis) and intracavitary (pleural and peritoneal carcinosis) applications yields good results. The radiophosphorus therapy in polycythemia vera rubra has always to be considered as an alternative to chemotherapy. The use of analgetics may be reduced by pain therapy of bone metastasis by injection of bone-seeking beta emitters like Rh-186 HEDP. Other procedures like therapeutic application of meta-iodo-benzylguanidine in neuroblastoma and malignant pheochromocytoma resulted in at least remissions of the disease. Radioimmunotherapy needs further evaluation before it can be recommended as a routine procedure. (orig.) [de

  1. Significant Radionuclides Determination

    Energy Technology Data Exchange (ETDEWEB)

    Jo A. Ziegler

    2001-07-31

    The purpose of this calculation is to identify radionuclides that are significant to offsite doses from potential preclosure events for spent nuclear fuel (SNF) and high-level radioactive waste expected to be received at the potential Monitored Geologic Repository (MGR). In this calculation, high-level radioactive waste is included in references to DOE SNF. A previous document, ''DOE SNF DBE Offsite Dose Calculations'' (CRWMS M&O 1999b), calculated the source terms and offsite doses for Department of Energy (DOE) and Naval SNF for use in design basis event analyses. This calculation reproduces only DOE SNF work (i.e., no naval SNF work is included in this calculation) created in ''DOE SNF DBE Offsite Dose Calculations'' and expands the calculation to include DOE SNF expected to produce a high dose consequence (even though the quantity of the SNF is expected to be small) and SNF owned by commercial nuclear power producers. The calculation does not address any specific off-normal/DBE event scenarios for receiving, handling, or packaging of SNF. The results of this calculation are developed for comparative analysis to establish the important radionuclides and do not represent the final source terms to be used for license application. This calculation will be used as input to preclosure safety analyses and is performed in accordance with procedure AP-3.12Q, ''Calculations'', and is subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (DOE 2000) as determined by the activity evaluation contained in ''Technical Work Plan for: Preclosure Safety Analysis, TWP-MGR-SE-000010'' (CRWMS M&O 2000b) in accordance with procedure AP-2.21Q, ''Quality Determinations and Planning for Scientific, Engineering, and Regulatory Compliance Activities''.

  2. Radionuclide calibrators performance evaluation

    International Nuclear Information System (INIS)

    Mora Ramirez, E.; Zeledon Fonseca, P.; Jimenez Cordero, M.

    2008-01-01

    Radionuclide calibrators are used to estimate accurately activity prior to administration to a patient, so it is very important that this equipment meets its performance requirements. The purpose of this paper is to compare the commercially available 'Calicheck' (Calcorp. Inc), used to assess linearity, versus the well-known source decay method, and also to show our results after performing several recommended quality control tests. The parameters that we wanted to evaluate were carried on using the Capintec CRC-15R and CRC-15 β radionuclide calibrators. The evaluated tests were: high voltage, display, zero adjust, background, reproducibility, source constancy, accuracy, precision and linearity. The first six tests were evaluated on the daily practice, here we analyzed the 2007 recorded data; and the last three were evaluated once a year. During the daily evaluation both calibrators performance were satisfactory comparing with the manufacture's requirements. The accuracy test show result within the ± 10% allowed for a field instrument. Precision performance is within the ± 1 % allowed. On the other hand, the linearity test shows that using the source decay method the relative coefficient is 0.9998, for both equipment and using the Calicheck the relative coefficient is 0.997. However, looking the percentage of error, during the 'Calicheck' test, its range goes from 0.0 % up to -25.35%, and using the source decay method, the range goes from 0.0 % up to -31.05 %, taking into account both instruments. Checking the 'Calicheck' results we can see that the results varying randomly, but using the source decay method the percentage of error increase as the source activity decrease. We conclude that both devices meet its manufactures requirements, in the case of the linearity using the decay method, decreasing the activity source, increasing the percentage of error, this may happen because of the equipment age. (author)

  3. Nanotargeted Radionuclides for Cancer Nuclear Imaging and Internal Radiotherapy

    Directory of Open Access Journals (Sweden)

    Gann Ting

    2010-01-01

    Full Text Available Current progress in nanomedicine has exploited the possibility of designing tumor-targeted nanocarriers being able to deliver radionuclide payloads in a site or molecular selective manner to improve the efficacy and safety of cancer imaging and therapy. Radionuclides of auger electron-, α-, β-, and γ-radiation emitters have been surface-bioconjugated or after-loaded in nanoparticles to improve the efficacy and reduce the toxicity of cancer imaging and therapy in preclinical and clinical studies. This article provides a brief overview of current status of applications, advantages, problems, up-to-date research and development, and future prospects of nanotargeted radionuclides in cancer nuclear imaging and radiotherapy. Passive and active nanotargeting delivery of radionuclides with illustrating examples for tumor imaging and therapy are reviewed and summarized. Research on combing different modes of selective delivery of radionuclides through nanocarriers targeted delivery for tumor imaging and therapy offers the new possibility of large increases in cancer diagnostic efficacy and therapeutic index. However, further efforts and challenges in preclinical and clinical efficacy and toxicity studies are required to translate those advanced technologies to the clinical applications for cancer patients.

  4. Developing spatial biophysical accounting for multiple ecosystem services

    NARCIS (Netherlands)

    Remme, R.P.; Schroter, M.; Hein, L.G.

    2014-01-01

    Ecosystem accounting is receiving increasing interest as a way to systematically monitor the conditions of ecosystems and the ecosystem services they provide. A critical element of ecosystem accounting is understanding spatially explicit flows of ecosystem services. We developed spatial biophysical

  5. Developing a protocol for managing the biophysical condition of a ...

    African Journals Online (AJOL)

    Their function will focus on the overall management of water resources on a ... for the integrated management of the biophysical component of a catchment, with ... and implement a protocol which will combine and integrate the knowledge of ...

  6. Biophysical approach to low back pain: a pilot report

    Czech Academy of Sciences Publication Activity Database

    Foletti, A.; Pokorný, Jiří

    2015-01-01

    Roč. 34, č. 2 (2015), s. 156-159 ISSN 1536-8378 Institutional support: RVO:67985882 Keywords : Bioelectromagnetic medicine * Biophysical therapy * Coherence domains Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 1.208, year: 2015

  7. Geomorphological applications of environmental radionuclides

    International Nuclear Information System (INIS)

    Quine, T.A.; Walling, D.

    1998-01-01

    Geomorphologists have shown increasing interest in environmental radionuclides since pioneering studies by Ritchie and McHenry in the USA and Campbell, Longmore and Loughran in Australia. Environmental radionuclides have attracted this interest because they provide geomorphologists with the means to trace sediment movement within the landscape. They, therefore, facilitate investigation of subjects at the core of geomorphology, namely the rates and patterns of landscape change. Most attention has been focussed on the artificial radionuclide caesium-137 ( 137 Cs) but more recently potential applications of the natural radionuclides lead-210 ( 210 Pb) and beryllium-7( 7 Be) have been investigated (Walling et al., 1995; Wallbrink and Murray, 1996a, 1996b). The origin, characteristics and applications of these radionuclides are summarised. These radionuclides are of value as sediment tracers because of three important characteristics: a strong affinity for sediment; a global distribution and the possibility of measurement at low concentration. Geomorphological applications of environmental radionuclides provide unique access to detailed qualitative data concerning landscape change over a range of timescales

  8. Molecular Targets for Targeted Radionuclide Therapy

    International Nuclear Information System (INIS)

    Mather, S.J.

    2009-01-01

    Molecular targeted radionuclide cancer therapy is becoming of increasing importance, especially for disseminated diseases. Systemic chemotherapies often lack selectivity while targeted radionuclide therapy has important advantages as the radioactive cytotoxic unit of the targeting vector is specifically directed to the cancer, sparing normal tissues. The principle strategy to improve cancer selectivity is to couple therapeutic agents to tumour-targeting vectors. In targeted radionuclide therapy (TRT), the cytotoxic portion of the conjugates normally contains a therapeutic radiometal immobilised by a bifunctional chelator. The aim is therefore to use as ligand-targeted therapeutics vectors coupled to Auger-, alpha- and/or beta-emitting radionuclides. An advantage of using radiation instead of chemotherapeutics as the cytotoxic agent is the so called 'crossfire effect'. This allows sterilisation of tumour cells that are not directly targeted due to heterogeneity in target molecule expression or inhomogeneous vector delivery. However, before the targeting ligands can be selected, the target molecule on the tumour has to be selected. It should be uniquely expressed, or at least highly overexpressed, on or in the target cells relative to normal tissues. The target should be easily accessible for ligand delivery and should not be shed or down- regulated after ligand binding. An important property of a receptor (or antigen) is its potential to be internalized upon binding of the ligand. This provides an active uptake mechanism and allows the therapeutic agent to be trapped within the tumour cells. Molecular targets of current interest include: Receptors: G-protein coupled receptors are overexpressed on many major human tumours. The prototype of these receptors are somatostatin receptors which show very high density in neuroendocrine tumours, but there are many other most interesting receptors to be applied for TRT. The targeting ligands for these receptors are

  9. Biophysical Influence of Airborne Carbon Nanomaterials on Natural Pulmonary Surfactant

    OpenAIRE

    Valle, Russell P.; Wu, Tony; Zuo, Yi Y.

    2015-01-01

    Inhalation of nanoparticles (NP), including lightweight airborne carbonaceous nanomaterials (CNM), poses a direct and systemic health threat to those who handle them. Inhaled NP penetrate deep pulmonary structures in which they first interact with the pulmonary surfactant (PS) lining at the alveolar air–water interface. In spite of many research efforts, there is a gap of knowledge between in vitro biophysical study and in vivo inhalation toxicology since all existing biophysical models handl...

  10. The relationship between fetal biophysical profile and cord blood PH

    Directory of Open Access Journals (Sweden)

    Valadan M

    2009-02-01

    Full Text Available "nBackground: The Biophysical Profile (BPP is a noninvasive test that predicts the presence or absence of fetal asphyxia and, ultimately, the risk of fetal death in the antenatal period. Intervention on the basis of an abnormal biophysical profile result has been reported to yield a significant reduction in prenatal mortality, and an association exists between biophysical profile scoring and a decreased cerebral palsy rate in a given population. The BPP evaluates five characteristics: fetal movement, tone, breathing, heart reactivity, and amniotic fluid (AF volume estimation. The purpose of study was to determine whether there are different degree of acidosis at which the biophysical activity (acute marker are affected. "nMethods: In a prospective study of 140 patients undergoing cesarean section before onset of labor, the fetal biophysical profile was performed 24h before the time of cesarean and was matched with cord arterial PH that was obtained from a cord segment (10-20cm that was double clamped after delivery of newborn. (using cord arterial PH less than 7.20 for the diagnosis of acidosis. "nResults: The fetal biophysical profile was found to have a significant relationship with umbilical blood PH. The sensitivity, specificity, positive predictive value, negative predictive value of fetal biophysical profile score were: 88.9%, 88.6%, 50%, 98.1%. "nConclusion: The first manifestations of fetal acidosis are nonreactive nonstress testing and fetal breathing loss; in advanced acidemia fetal movements and fetal tone are compromised. A protocol of antepartum fetal evaluation is suggested based upon the individual biophysical components rather than the score alone.

  11. Biophysics of Human Hair Structural, Nanomechanical, and Nanotribological Studies

    CERN Document Server

    Bhushan, Bharat

    2010-01-01

    This book presents the biophysics of hair. It deals with the structure of hair, its mechanical properties, the nanomechanical characterization, tensile deformation, tribological characterization, the thickness distribution and binding interactions on hair surface. Another important topic of the book is the health of hair, human hair and skin, hair care, cleaning and conditioning treatments and damaging processes. It is the first book on the biophysical properties of hair.

  12. Radionuclides in Canada goose eggs

    International Nuclear Information System (INIS)

    Rickard, W.H.; Sweany, H.A.

    1975-01-01

    Low levels of radionuclides were measured in Canada goose eggs taken from deserted nests from Columbia River islands on the Energy Research and Development Administration's Hanford Reservation. Potassium-40, a naturally occurring radionuclide, was the most abundant radionuclide measured in egg contents and egg shell. Strontium-90 was incorporated into egg shells and cesium-137 into inner egg contents. Manganese-54, cobalt-60, and zinc-65 were more abundant in inner egg contents than in egg shell. Cerium-144 was detected in egg shell but not in inner shell

  13. Radionuclide migration in water reservoirs

    International Nuclear Information System (INIS)

    Rodionova, L.F.

    1983-01-01

    Toxicity degree and radiation effect of different radionuclides depend on multiple factors, whose interaction can strengthen or weaken the effects through the mechanism of nuclide accumulation by hydrobiontes. Stage of development of an aquatic organism, its age, mass and sex as well as lifetime and residence time of the organism in the given medium are of importance. The radionuclide build up depends on illumination, locale of the bioobject residence, on the residence nature. The concentration of radionuclides in aquatic organisms and bionts survival depend on a season, temperature of the residence medium, as well as salinity and mineral composition of water influence

  14. Chemonuclear studies for identification for new production routes for the therapeutically useful radionuclides {sup 140}Nd, {sup 192}Ir, {sup 191}Pt, {sup 193m}Pt, und {sup 195m}Pt; Kernchemische Studien zur Entwicklung neuerer Produktionsverfahren fuer die therapierelevanten Radionuklide {sup 140}Nd, {sup 192}Ir, {sup 191}Pt, {sup 193m}Pt, und {sup 195m}Pt

    Energy Technology Data Exchange (ETDEWEB)

    Hilgers, K.

    2005-12-15

    New production routes for the therapeutically useful radionuclides {sup 140}Nd, {sup 192}Ir, {sup 191}Pt, {sup 193m}Pt and {sup 195m}Pt were investigated. Cross section data were measured using the stacked-foil technique and compared with theoretical calculations. A production method for the platinum nuclides was developed. The {sup 141}Pr(p, 2n){sup 140}Nd and {sup nat}Ce({sup 3}He, xn){sup 140}Nd reactions were investigated for production of {sup 140}Nd. Cross section data of nuclear reactions leading to the side products {sup 141}Nd, {sup 139}Nd and {sup 139}Ce could also be achieved. The experimental data were compared with theoretical calculations using the code ALICE-IPPE. A comparison of the calculated thick target yields showed that the {sup 141}Pr(p, 2n){sup 140}Nd reaction gives a higher yield. The {sup 192}Os(p, n){sup 192}Ir reaction was examined in the context of the production of {sup 192}Ir. Cross section data were determined and compared with theoretical calculations using the codes ALICE-IPPE and EMPIRE II. The yield of this reaction was compared with the yield of the reactor production of this nuclide. The reactor production seems to be more suitable because of a higher purity and yield. Cross section data were measured for the {sup 192}Os({alpha}, n){sup 195m}Pt, {sup 192}Os({alpha}, 3n){sup 193m}Pt and {sup 192}Os({sup 3}He, 4n){sup 191}Pt reactions. The activity of {sup 193m}Pt and {sup 195m}Pt was determined by X-ray spectroscopy after a chemical separation procedure. The ALICE-IPPE code was found to be inappropriate to reproduce the experimental values. The calculated yields were compared with the yields of other reactions, especially the reactor production of {sup 195m}Pt. The yield of the {sup 192}Os({alpha}, n){sup 195m}Pt reaction is lower compared to the yield of the reactor production, but offers lower target costs and higher specific activity. A production method for {sup 193m}Pt and {sup 195m}Pt was developed. Batch yields of 0.9 MBq

  15. [Biophysical principles of collagen cross-linking].

    Science.gov (United States)

    Spörl, E; Raiskup-Wolf, F; Pillunat, L E

    2008-02-01

    The reduced mechanical stability of the cornea in keratoconus or in keratectasia after Lasik may be increased by photooxidative cross-linking of corneal collagen. The biophysical principles are compiled for the safe and effective application of this new treatment method. The setting of the therapy parameters should be elucidated from the absorption behaviour of the cornea. The safety of the method for the endothelium cells and the lens will be discussed. The induced cross-links are shown to be the result of changes in the physico-chemical properties of the cornea. To reach a high absorption of the irradiation energy in the cornea, riboflavin of a concentration of 0.1% and UV light of a wavelength of 370 nm, corresponding to the relative maximum of absorption of riboflavin, were used. An irradiance of 3 mW/cm(2) and an irradiation time of 30 min lead to an increase of the mechanical stiffness. The endothelium cells will be protected due to the high absorption within the cornea, that means the damaging threshold of the endothelium cells will not be reached in a 400 microm thick stroma. As evidence for cross-links we can consider the increase of the biomechanical stiffness, the increased resistance against enzymatic degradation, a higher shrinkage temperature, a lower swelling rate and an increased diameter of collagen fibres. The therapy parameters were tested experimentally and have been proven clinically in the corneal collagen cross-linking. These parameters should be respected to reach a safe cross-linking effect without damage of the adjacent tissues.

  16. Smoothing of, and parameter estimation from, noisy biophysical recordings.

    Directory of Open Access Journals (Sweden)

    Quentin J M Huys

    2009-05-01

    Full Text Available Biophysically detailed models of single cells are difficult to fit to real data. Recent advances in imaging techniques allow simultaneous access to various intracellular variables, and these data can be used to significantly facilitate the modelling task. These data, however, are noisy, and current approaches to building biophysically detailed models are not designed to deal with this. We extend previous techniques to take the noisy nature of the measurements into account. Sequential Monte Carlo ("particle filtering" methods, in combination with a detailed biophysical description of a cell, are used for principled, model-based smoothing of noisy recording data. We also provide an alternative formulation of smoothing where the neural nonlinearities are estimated in a non-parametric manner. Biophysically important parameters of detailed models (such as channel densities, intercompartmental conductances, input resistances, and observation noise are inferred automatically from noisy data via expectation-maximization. Overall, we find that model-based smoothing is a powerful, robust technique for smoothing of noisy biophysical data and for inference of biophysical parameters in the face of recording noise.

  17. Macromolecular therapeutics.

    Science.gov (United States)

    Yang, Jiyuan; Kopeček, Jindřich

    2014-09-28

    This review covers water-soluble polymer-drug conjugates and macromolecules that possess biological activity without attached low molecular weight drugs. The main design principles of traditional and backbone degradable polymer-drug conjugates as well as the development of a new paradigm in nanomedicines - (low molecular weight) drug-free macromolecular therapeutics are discussed. To address the biological features of cancer, macromolecular therapeutics directed to stem/progenitor cells and the tumor microenvironment are deliberated. Finally, the future perspectives of the field are briefly debated. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Artificial radionuclides in soil, flora and fauna

    International Nuclear Information System (INIS)

    Marej, A.N.

    1984-01-01

    Sources and ways of soil contamination by radionuclides, as well as the main regularities of radionuclide behaviour in soils, are discussed. Ways of radionuclide uptake by plants are discussed in detail, since radionuclide contamination of vegetation, and agricultural plants and pastures in particular, is one of the main factors, determining sanitary value of environmental contamination by radioactive substances

  19. The development and use of radionuclide generators in nuclear medicine. Recent advances and future perspectives

    International Nuclear Information System (INIS)

    Knapp, F.F. Jr.

    1998-01-01

    Although the trend in radionuclide generator research has declined, radionuclide generator systems continue to play an important role in nuclear medicine. Technetium-99m obtained from the molybdenum-99/technetium-99m generator system is used in over 80 per cent of all diagnostic clinical studies and there is increasing interest and use of therapeutic radioisotopes obtained from generator systems. This paper focuses on a discussion of the major current areas of radionuclide generator research, and the expected areas of future research and application. (author)

  20. Quality control of radionuclide calibrators used in nuclear medicine services in the Brazilian northeast region

    International Nuclear Information System (INIS)

    Fragoso, Maria C.F.; Albuquerque, Antonio M.S.; Oliveira, Mercia L.; Lima, Ricardo A.; Lima, Fabiana F.

    2011-01-01

    The radionuclide calibrators are essential instruments in nuclear medicine services in order to activity determination of radiopharmaceuticals which will be administered to the patients. Inappropriate performance of these equipment could provide underestimation or overestimation of the activity, compromising the success of diagnosis or therapeutic procedures. To ensure the satisfactory performance of the radionuclide calibrators, quality control tests are recommended by national and international guides. The aim of this work was evaluate the establishment of the quality control program in the radionuclide calibrators at medicine nuclear services in the Brazilian northeast region, highlighting the tests and their frequencies. (author)

  1. Radionuclides and the normal bone scan

    International Nuclear Information System (INIS)

    Mettler, F.A. Jr.; Monsein, L.; Rosenberg, R.D.

    1988-01-01

    Recently, Eisenhut and co-workers have described development of iodine-131 labeled diphosphonates for palliative treatment of bone metastases. The compound labeled was alpha-amino (4-hydroxybenzylidene) diphosphonate (BDP3). Other beta-emitting radionuclides have been used for treatment of intractable pain secondary to bone metastases. These include strontium-89, which has some difficulties, particularly in terms of disposal of the excretions due to the long physical half-life of the life of the radionuclide. Yttrium-90 has also been used but has a relatively high hepatic uptake. Phosphorus-32 labeled compounds have also been used. Although palliation has been described, bone marrow depression has also occurred. Rhenium-186 also has been suggested, however, high renal uptake is a problem. At present, the iodine-131 labeled BDP3 appears to be the best of the available therapeutic radiopharmaceuticals. One of the major disadvantages in use of this compound is the production of gamma photons. While undesirable from a dosimetry viewpoint, gamma photons do, however, permit imaging if desired

  2. Radionuclide methods in pediatric cardiology

    International Nuclear Information System (INIS)

    Reich, O.; Ruth, C.; Samanek, M.

    1990-01-01

    The use of radionuclide methods in pediatric cardiology is discussed for non-invasive evaluation of myocardial function and perfusion, regional lung perfusion and ventilation, and for measuring central and peripheral hemodynamics. (H.W.). 16 refs

  3. Radionuclide Retention in Concrete Wasteforms

    Energy Technology Data Exchange (ETDEWEB)

    Bovaird, Chase C.; Jansik, Danielle P.; Wellman, Dawn M.; Wood, Marcus I.

    2011-09-30

    Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. The information present in the report provides data that (1) measures the effect of concrete wasteform properties likely to influence radionuclide migration; and (2) quantifies the rate of carbonation of concrete materials in a simulated vadose zone repository.

  4. Radionuclides in the food chain

    International Nuclear Information System (INIS)

    Harley, J.H.; Schmidt, G.D.

    1988-01-01

    Radionuclides in the Food Chain reviews past experience in meeting the challenge of radionuclide contamination of foodstuffs and water sources and, in the wake of the reactor accidents at Chernobyl and Three Mile Island, presents current concepts and programs relating to measurement, surveillance, effects, risk management, evaluation guidelines, and control and regulatory activities. This volume, based on a symposium sponsored by the International Life Sciences Institute in association with the International Institute for Applied Systems Analysis, which brought together both radiation experts and food industry policymakers, examines such vital topics as structural problems in large-scale crisis-managment systems; dose assessment from man-made sources; international recommendations on radiation protection; airborne contamination, as well as aquatic and soilborne radionuclides; food-chain contamination from testing nuclear devices; long-term health effects of radionuclides in food and water supplies; and use of mathematical models in risk assessment and management. (orig.)

  5. Drift-Scale Radionuclide Transport

    International Nuclear Information System (INIS)

    Houseworth, J.

    2004-01-01

    The purpose of this model report is to document the drift scale radionuclide transport model, taking into account the effects of emplacement drifts on flow and transport in the vicinity of the drift, which are not captured in the mountain-scale unsaturated zone (UZ) flow and transport models ''UZ Flow Models and Submodels'' (BSC 2004 [DIRS 169861]), ''Radionuclide Transport Models Under Ambient Conditions'' (BSC 2004 [DIRS 164500]), and ''Particle Tracking Model and Abstraction of Transport Process'' (BSC 2004 [DIRS 170041]). The drift scale radionuclide transport model is intended to be used as an alternative model for comparison with the engineered barrier system (EBS) radionuclide transport model ''EBS Radionuclide Transport Abstraction'' (BSC 2004 [DIRS 169868]). For that purpose, two alternative models have been developed for drift-scale radionuclide transport. One of the alternative models is a dual continuum flow and transport model called the drift shadow model. The effects of variations in the flow field and fracture-matrix interaction in the vicinity of a waste emplacement drift are investigated through sensitivity studies using the drift shadow model (Houseworth et al. 2003 [DIRS 164394]). In this model, the flow is significantly perturbed (reduced) beneath the waste emplacement drifts. However, comparisons of transport in this perturbed flow field with transport in an unperturbed flow field show similar results if the transport is initiated in the rock matrix. This has led to a second alternative model, called the fracture-matrix partitioning model, that focuses on the partitioning of radionuclide transport between the fractures and matrix upon exiting the waste emplacement drift. The fracture-matrix partitioning model computes the partitioning, between fractures and matrix, of diffusive radionuclide transport from the invert (for drifts without seepage) into the rock water. The invert is the structure constructed in a drift to provide the floor of the

  6. Radionuclides and maternal lactation

    International Nuclear Information System (INIS)

    Zamora, H.H.

    1989-01-01

    The increase in the number of nuclear medicine centers, both official and private in the country, as well as the increase in the number of patients, due to the effectiveness of their diagnostic and therapeutic procedures, brings out new situations that must be studied from the point of view of radioprotection. This work makes a revision in the medical literature about procedures with radioisotopes during the maternal nursing period. In general, it is recommended to stop nursing for 24 hours for 99mtc test, and to resume it after the draining of the milky content. This can be done in spite of the sensitivity of the target organ of the baby, because the dosage will be below permissible limits accepted by international agencies with respect to diagnostic test and I-131 treatment, and if continuing nursing is desired, it is recommended to use other diagnostic or therapeutic procedures before discontinuing the most important nutritional resource at this age

  7. Surface diffusion of sorbed radionuclides

    International Nuclear Information System (INIS)

    Berry, J.A.; Bond, K.A.

    1991-01-01

    Surface diffusion has in the past been invoked to explain rates of radionuclide migration which were greater than those predicted. Results were generally open to interpretation but the possible existence of surface diffusion, whereby sorbed radionuclides could potentially migrate at much enhanced rates, necessitated investigation. In this work through-diffusion experiments have shown that although surface diffusion does exist for some nuclides, the magnitude of the phenomenon is not sufficient to affect repository safety assessment modelling. (author)

  8. Radionuclide generators for biomedical applications

    International Nuclear Information System (INIS)

    Finn, R.D.; Molinski, V.J.; Hupf, H.B.; Kramer, H.

    1983-10-01

    This document reviews the chemical literature of those radionuclide generators that have gained or appear to possess utility in medical imaging. The text represents a conscientious effort to peruse the scientific literature through 1980. The intent of this work is to provide a reference point for the investigator who is interested in the development of a particular generator system and the refinements which have been reported. Moreover, the incorporation of the particular daughter radionuclide into a suitable radiodiagnostic agent is presented

  9. Loading technique for preparing radionuclide containing nanoparticles

    DEFF Research Database (Denmark)

    2011-01-01

    associated with leaky blood vessels. The composition and methods of the invention find particular use in diagnosing and imaging cancerous tissue and, in general, pathological conditions associated with leaky blood vessels in a subject. The present invention provides a new diagnostic tool for the utilization......Source: US2012213698A The present invention relates to a novel composition and method for loading delivery systems such as liposome compositions with radionuclides useful in targeted diagnostic and/or therapy of target site, such as cancerous tissue and, in general, pathological conditions...... of positron emission tomography (PET) imaging technique. One specific aspect of the invention is directed to a method of producing nanoparticles with desired targeting properties for diagnostic and/or radio-therapeutic applications....

  10. Prospects for the methods of radionuclide production

    International Nuclear Information System (INIS)

    Karamyan, S.A.; Dmitriev, S.N.

    2014-01-01

    Methods of radionuclide production for the nuclear-medicine purposes are described. In a budget approach, the application of low-energy accelerators is especially advantageous. Intense flux of bremsstrahlung at electron accelerators or high-current cyclotron beams of alpha particles must supply a great yield for many isotopes. The choice of a target material and of the projectile energy provides enough variation for concrete species formation. The innovating procedures are here proposed for optimizing of methods, for instance, application of the noble-gas target for production and transport of activities. The known and new variants of the 'generator' scheme are discussed. Many isotopes are listed as promising in the context of the therapeutic and theragnostic applications. Among them are isotopes/isomers emitting soft radiation for the selective and careful body treatment, also the positron emitters for PET, and the halogen and alkali-metal species convenient for chemical separation.

  11. Therapeutic Nanodevices

    Science.gov (United States)

    Lee, Stephen; Ruegsegger, Mark; Barnes, Philip; Smith, Bryan; Ferrari, Mauro

    Therapeutic nanotechnology offers minimally invasive therapies with high densities of function concentrated in small volumes, features that may reduce patient morbidity and mortality. Unlike other areas of nanotechnology, novel physical properties associated with nanoscale dimensionality are not the raison d'être of therapeutic nanotechnology, whereas the aggregation of multiple biochemical (or comparably precise) functions into controlled nanoarchitectures is. Multifunctionality is a hallmark of emerging nanotherapeutic devices, and multifunctionality can allow nanotherapeutic devices to perform multistep work processes, with each functional component contributing to one or more nanodevice subroutine such that, in aggregate, subroutines sum to a cogent work process. Cannonical nanotherapeutic subroutines include tethering (targeting) to sites of disease, dispensing measured doses of drug (or bioactive compound), detection of residual disease after therapy and communication with an external clinician/operator. Emerging nanotherapeutics thus blur the boundaries between medical devices and traditional pharmaceuticals. Assembly of therapeutic nanodevices generally exploits either (bio)material self-assembly properties or chemoselective bioconjugation techniques, or both. Given the complexity, composition, and the necessity for their tight chemical and structural definition inherent in the nature of nanotherapeutics, their cost of goods (COGs) might exceed that of (already expensive) biologics. Early therapeutic nanodevices will likely be applied to disease states which exhibit significant unmet patient need (cancer and cardiovascular disease), while application to other disease states well-served by conventional therapy may await perfection of nanotherapeutic design and assembly protocols.

  12. Radionuclide migration in soils

    Energy Technology Data Exchange (ETDEWEB)

    Demir, M [Ingenieurgesellschaft Bonnenberg und Drescher, Juelich (Germany, F.R.)

    1979-01-01

    Unplanned releases from a nuclear installation - e.g., leakage from a storage tank or other incident - can result in the escape of contaminants such as U, Pu, Cs, Sr, T etc. Nuclide transport through the ground is governed by characteristics of the subsurface hydrology and the specific nuclides under consideration. Unsaturated soil layers result in a transport rate so low as to negligible. Radionuclides reaching the ground water are assumed to endanger human life because of potential uncontrolled ingestion. The most dangerous nuclides are long-lived and not absorbed, or very poorly absorbed, in the soil. During migration of nuclides through saturated soil layers, the concentration can be reduced by dilution. Preliminary results indicate that tritium is spread with ground water velocity. Its concentration can be reduced only by diffusion, dispersion and radioactive decay. Alpha-emitters are strongly retained velocities of alpha-emitters are approximately one thousandth (10/sup -3/) that of T. Transport velocities of Cs and Sr are approximately one hundreth (10/sup -2/) and one tenth (10/sup -1/) that of T respectively.

  13. Radionuclide migration in soils

    International Nuclear Information System (INIS)

    Demir, M.

    1979-01-01

    Unplanned releases from a nuclear installation - e.g., leakage from a storage tank or other incident - can result in the escape of contaminants such as U, Pu, Cs, Sr, T etc. Nuclide transport through the ground is governed by characteristics of the subsurface hydrology and the specific nuclides under consideration. Unsaturated soil layers result in a transport rate so low as to negligible. Radionuclides reaching the ground water are assumed to endanger human life because of potential uncontrolled ingestion. The most dangerous nuclides are long-lived and not absorbed, or very poorly absorbed, in the soil. During migration of nuclides through saturated soil layers, the concentration can be reduced by dilution. Preliminary results indicate that tritium is spread with ground water velocity. Its concentration can be reduced only by diffusion, dispersion and radioactive decay. Alpha-emitters are strongly retained velocities of alpha-emitters are approximately one thousandth (10 -3 ) that of T. Transport velocities of Cs and Sr are approximately one hundreth (10 -2 ) and one tenth (10 -1 ) that of T respectively. (orig./HP) [de

  14. Radionuclide salivary gland imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mishkin, F.S.

    1981-10-01

    Salivary gland imaging with 99mTc as pertechnetate provides functional information concerning trapping and excretion of the parotid and submandibular glands. Anatomic information gained often adds little to clinical evaluation. On the other hand, functional information may detect subclinical involvement, which correlates well with biopsy of the minor labial salivary glands. Salivary gland abnormalities in systemic disease such as sarcoidosis, rheumatoid arthritis, lupus erythematosus, and other collagenvascular disorders may be detected before they result in the clinical manifestaions of Sjoegren's syndrome. Such glands, after initially demonstrating increased trapping in the acute phase, tend to have decreased trapping and failure to discharge pertechnetate in response to an appropriate physiologic stimulus. Increased uptake of gallium-67 citrate often accompanies these findings. Inflammatory parotitis can be suspected when increased perfusion is evident on radionuclide angiography with any agent. The ability of the salivary gland image to detect and categorize mass lesions, which result in focal areas of diminished activity such as tumors, cysts, and most other masses, is disappointing, while its ability to detect and categorize Warthin's tumor, which concentrates pertechnetate, is much more valuable, although not specific.

  15. Radionuclide brain scanning

    International Nuclear Information System (INIS)

    Abdel-Dayem, H.

    1992-01-01

    At one stage of medical imaging development, radionuclide brain scanning was the only technique available for imaging of the brain. Advent of CT and MRI pushed it to the background. It regained some of the grounds lost to ''allied advances'' with the introduction of brain perfusion radiopharmaceuticals. Positron emission tomography is a promising functional imaging modality that at present will remain as a research tool in special centres in developed countries. However, clinically useful developments will gradually percolate from PET to SPECT. The non-nuclear imaging methods are totally instrument dependent; they are somewhat like escalators, which can go that far and no further. Nuclear imaging has an unlimited scope for advance because of the new developments in radiopharmaceuticals. As the introduction of a radiopharmaceutical is less costly than buying new instruments, the recent advances in nuclear imaging are gradually perfusing through the developing countries also. Therefore, it is essential to follow very closely PET developments because what is research today might become routine tomorrow

  16. Radionuclides migration or isolation?

    International Nuclear Information System (INIS)

    Toulhoat, P.; Grambow, B.; Simoni, E.

    2005-01-01

    After 20 years of research, the chemical behaviour of actinides and fission products in nuclear waste disposal environments is much better understood. Consistent thermodynamic data have been gathered and allow much more accurate previsions. Through the considerable development of analytical spectroscopy, including time resolved laser fluorescence and X ray absorption, a better understanding of the chemical reactivity (complexation, sorption) of actinides and fission products at a molecular scale has been possible. Chemically reducing conditions are found in most selected disposal host rock formations, generally chosen for their high sorption capacity (clays); such conditions favour the chemical confinement of most radionuclides through precipitation or sorption. Low permeability host rocks participate to this confinement, as convective fluxes are lower than diffusive fluxes. The most recent performance assessment exercises have taken into account the recent progress of knowledge in the chemical evolution of the near field. They show that the dose rates at the outlet are far lower than existing recommendations for normal and most altered evolution scenarios. (authors)

  17. Radionuclide salivary gland imaging

    International Nuclear Information System (INIS)

    Mishkin, F.S.

    1981-01-01

    Salivary gland imaging with 99mTc as pertechnetate provides functional information concerning trapping and excretion of the parotid and submandibular glands. Anatomic information gained often adds little to clinical evaluation. On the other hand, functional information may detect subclinical involvement, which correlates well with biopsy of the minor labial salivary glands. Salivary gland abnormalities in systemic disease such as sarcoidosis, rheumatoid arthritis, lupus erythematosus, and other collagenvascular disorders may be detected before they result in the clinical manifestaions of Sjoegren's syndrome. Such glands, after initially demonstrating increased trapping in the acute phase, tend to have decreased trapping and failure to discharge pertechnetate in response to an appropriate physiologic stimulus. Increased uptake of gallium-67 citrate often accompanies these findings. Inflammatory parotitis can be suspected when increased perfusion is evident on radionuclide angiography with any agent. The ability of the salivary gland image to detect and categorize mass lesions, which result in focal areas of diminished activity such as tumors, cysts, and most other masses, is disappointing, while its ability to detect and categorize Warthin's tumor, which concentrates pertechnetate, is much more valuable, although not specific

  18. Radionuclide brain scanning

    Energy Technology Data Exchange (ETDEWEB)

    Abdel-Dayem, H

    1993-12-31

    At one stage of medical imaging development, radionuclide brain scanning was the only technique available for imaging of the brain. Advent of CT and MRI pushed it to the background. It regained some of the grounds lost to ``allied advances`` with the introduction of brain perfusion radiopharmaceuticals. Positron emission tomography is a promising functional imaging modality that at present will remain as a research tool in special centres in developed countries. However, clinically useful developments will gradually percolate from PET to SPECT. The non-nuclear imaging methods are totally instrument dependent; they are somewhat like escalators, which can go that far and no further. Nuclear imaging has an unlimited scope for advance because of the new developments in radiopharmaceuticals. As the introduction of a radiopharmaceutical is less costly than buying new instruments, the recent advances in nuclear imaging are gradually perfusing through the developing countries also. Therefore, it is essential to follow very closely PET developments because what is research today might become routine tomorrow

  19. Anthropogenic radionuclides in the environment

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Q; Weng, J; Wang, J

    2007-11-15

    Studies of radionuclides in the environment have entered a new era with the renaissance of nuclear energy and associated fuel reprocessing, geological disposal of high-level nuclear wastes, and concerns about national security with respect to nuclear non-proliferation. This work presents an overview of anthropogenic radionuclide contamination in the environment, as well as the salient geochemical behavior of important radionuclides. We first discuss the following major anthropogenic sources and current development that contribute to the radionuclide contamination of the environment: (1) nuclear weapons program; (2) nuclear weapons testing; (3) nuclear power plants; (4) commercial fuel reprocessing; (5) geological repository of high-level nuclear wastes, and (6) nuclear accidents. Then, we summarize the geochemical behavior for radionuclides {sup 99}Tc, {sup 129}I, and {sup 237}Np, because of their complex geochemical behavior, long half-lives, and presumably high mobility in the environment. Biogeochemical cycling and environment risk assessment must take into account speciation of these redox-sensitive radionuclides.

  20. Introduction to radiobiology of targeted radionuclide therapy

    Directory of Open Access Journals (Sweden)

    Jean-Pierre ePOUGET

    2015-03-01

    Full Text Available During the last decades, new radionuclide-based targeted therapies have emerged as efficient tools for cancer treatment. Targeted radionuclide therapies (TRT are based on a multidisciplinary approach that involves the cooperation of specialists in several research fields. Among them, radiobiologists investigate the biological effects of ionizing radiation, specifically the molecular and cellular mechanisms involved in the radiation response. Most of the knowledge about radiation effects concerns external beam radiation therapy (EBRT and radiobiology has then strongly contributed to the development of this therapeutic approach. Similarly, radiobiology and dosimetry are also assumed to be ways for improving TRT, in particular in the therapy of solid tumors which are radioresistant. However, extrapolation of EBRT radiobiology to TRT is not straightforward. Indeed, the specific physical characteristics of TRT (heterogeneous and mixed irradiation, protracted exposure and low absorbed dose rate differ from those of conventional EBRT (homogeneous irradiation, short exposure and high absorbed dose rate, and consequently the response of irradiated tissues might be different. Therefore, specific TRT radiobiology needs to be explored. Determining dose-effect correlation is also a prerequisite for rigorous preclinical radiobiology studies because dosimetry provides the necessary referential to all TRT situations. It is required too for developing patient-tailored TRT in the clinic in order to estimate the best dose for tumor control, while protecting the healthy tissues, thereby improving therapeutic efficacy. Finally, it will allow to determine the relative contribution of targeted effects (assumed to be dose-related and non-targeted effects (assumed to be non-dose-related of ionizing radiation. However, conversely to EBRT where it is routinely used, dosimetry is still challenging in TRT. Therefore, it constitutes with radiobiology, one of the main

  1. MODELLING BIOPHYSICAL PARAMETERS OF MAIZE USING LANDSAT 8 TIME SERIES

    Directory of Open Access Journals (Sweden)

    T. Dahms

    2016-06-01

    Full Text Available Open and free access to multi-frequent high-resolution data (e.g. Sentinel – 2 will fortify agricultural applications based on satellite data. The temporal and spatial resolution of these remote sensing datasets directly affects the applicability of remote sensing methods, for instance a robust retrieving of biophysical parameters over the entire growing season with very high geometric resolution. In this study we use machine learning methods to predict biophysical parameters, namely the fraction of absorbed photosynthetic radiation (FPAR, the leaf area index (LAI and the chlorophyll content, from high resolution remote sensing. 30 Landsat 8 OLI scenes were available in our study region in Mecklenburg-Western Pomerania, Germany. In-situ data were weekly to bi-weekly collected on 18 maize plots throughout the summer season 2015. The study aims at an optimized prediction of biophysical parameters and the identification of the best explaining spectral bands and vegetation indices. For this purpose, we used the entire in-situ dataset from 24.03.2015 to 15.10.2015. Random forest and conditional inference forests were used because of their explicit strong exploratory and predictive character. Variable importance measures allowed for analysing the relation between the biophysical parameters with respect to the spectral response, and the performance of the two approaches over the plant stock evolvement. Classical random forest regression outreached the performance of conditional inference forests, in particular when modelling the biophysical parameters over the entire growing period. For example, modelling biophysical parameters of maize for the entire vegetation period using random forests yielded: FPAR: R² = 0.85; RMSE = 0.11; LAI: R² = 0.64; RMSE = 0.9 and chlorophyll content (SPAD: R² = 0.80; RMSE=4.9. Our results demonstrate the great potential in using machine-learning methods for the interpretation of long-term multi-frequent remote sensing

  2. Modelling Biophysical Parameters of Maize Using Landsat 8 Time Series

    Science.gov (United States)

    Dahms, Thorsten; Seissiger, Sylvia; Conrad, Christopher; Borg, Erik

    2016-06-01

    Open and free access to multi-frequent high-resolution data (e.g. Sentinel - 2) will fortify agricultural applications based on satellite data. The temporal and spatial resolution of these remote sensing datasets directly affects the applicability of remote sensing methods, for instance a robust retrieving of biophysical parameters over the entire growing season with very high geometric resolution. In this study we use machine learning methods to predict biophysical parameters, namely the fraction of absorbed photosynthetic radiation (FPAR), the leaf area index (LAI) and the chlorophyll content, from high resolution remote sensing. 30 Landsat 8 OLI scenes were available in our study region in Mecklenburg-Western Pomerania, Germany. In-situ data were weekly to bi-weekly collected on 18 maize plots throughout the summer season 2015. The study aims at an optimized prediction of biophysical parameters and the identification of the best explaining spectral bands and vegetation indices. For this purpose, we used the entire in-situ dataset from 24.03.2015 to 15.10.2015. Random forest and conditional inference forests were used because of their explicit strong exploratory and predictive character. Variable importance measures allowed for analysing the relation between the biophysical parameters with respect to the spectral response, and the performance of the two approaches over the plant stock evolvement. Classical random forest regression outreached the performance of conditional inference forests, in particular when modelling the biophysical parameters over the entire growing period. For example, modelling biophysical parameters of maize for the entire vegetation period using random forests yielded: FPAR: R² = 0.85; RMSE = 0.11; LAI: R² = 0.64; RMSE = 0.9 and chlorophyll content (SPAD): R² = 0.80; RMSE=4.9. Our results demonstrate the great potential in using machine-learning methods for the interpretation of long-term multi-frequent remote sensing datasets to model

  3. Cosmogenic radionuclides. Theory and applications in the terrestrial and space environments

    International Nuclear Information System (INIS)

    Beer, Juerg; Steiger, Rudolf von; McCracken, Ken

    2012-01-01

    Cosmogenic radionuclides are radioactive isotopes which are produced by natural processes and distributed within the Earth system. With a holistic view of the environment the authors show in this book how cosmogenic radionuclides can be used to trace and to reconstruct the history of a large variety of processes. They discuss the way in which cosmogenic radionuclides can assist in the quantification of complex processes in the present-day environment. The book aims to demonstrate to the reader the strength of analytic tools based on cosmogenic radionuclides, their contribution to almost any field of modern science, and how these tools may assist in the solution of many present and future problems that we face here on Earth. The book provides a comprehensive discussion of the basic principles behind the applications of cosmogenic (and other) radionuclides as environmental tracers and dating tools. The second section of the book discusses in some detail the production of radionuclides by cosmic radiation, their transport and distribution in the atmosphere and the hydrosphere, their storage in natural archives, and how they are measured. The third section of the book presents a number of examples selected to illustrate typical tracer and dating applications in a number of different spheres (atmosphere, hydrosphere, geosphere, biosphere, solar physics and astronomy). At the same time the authors have outlined the limitations of the use of cosmogenic radionuclides. Written on a level understandable by graduate students without specialist skills in physics or mathematics, the book addresses a wide audience, ranging from archaeology, biophysics, and geophysics, to atmospheric physics, hydrology, astrophysics and space science.

  4. Cosmogenic radionuclides. Theory and applications in the terrestrial and space environments

    Energy Technology Data Exchange (ETDEWEB)

    Beer, Juerg [Eidgenoessische Anstalt fuer Wasserversorgung, Abwasserreinigung und Gewaesserschutz, Duebendorf (Switzerland); Steiger, Rudolf von [International Space Science Insitute, Bern (Switzerland); McCracken, Ken [Maryland Univ., College Park (United States). IPST

    2012-07-01

    Cosmogenic radionuclides are radioactive isotopes which are produced by natural processes and distributed within the Earth system. With a holistic view of the environment the authors show in this book how cosmogenic radionuclides can be used to trace and to reconstruct the history of a large variety of processes. They discuss the way in which cosmogenic radionuclides can assist in the quantification of complex processes in the present-day environment. The book aims to demonstrate to the reader the strength of analytic tools based on cosmogenic radionuclides, their contribution to almost any field of modern science, and how these tools may assist in the solution of many present and future problems that we face here on Earth. The book provides a comprehensive discussion of the basic principles behind the applications of cosmogenic (and other) radionuclides as environmental tracers and dating tools. The second section of the book discusses in some detail the production of radionuclides by cosmic radiation, their transport and distribution in the atmosphere and the hydrosphere, their storage in natural archives, and how they are measured. The third section of the book presents a number of examples selected to illustrate typical tracer and dating applications in a number of different spheres (atmosphere, hydrosphere, geosphere, biosphere, solar physics and astronomy). At the same time the authors have outlined the limitations of the use of cosmogenic radionuclides. Written on a level understandable by graduate students without specialist skills in physics or mathematics, the book addresses a wide audience, ranging from archaeology, biophysics, and geophysics, to atmospheric physics, hydrology, astrophysics and space science.

  5. Radionuclide therapy for true polycythemia

    International Nuclear Information System (INIS)

    Afanasieva, N.I.; Grushka, G.V.; Vasiliev, L.Ya.

    2005-01-01

    Full text: True polycythemia (Vaquez' disease) is the disease of the hemopoietic system of an unknown origin accompanied by increase of erythrocyte count in the peripheral blood with absolute and relative increase in the mass of circulating erythrocytes. True polycythemia is treated with bloodletting and myelosuppressing drugs. This treatment is not always effective. A special place among myelo-depressants is occupied by P-32. Its main therapeutic effect is mediated by the participation in the metabolic processes. Besides DNA damage with beta-radiation, P-32 incorporation by DNA followed by decay and transformation to a stable sulphur isotope (S-32) results in the damage of the structure of nucleic acids, which is main mechanism of cellular proliferation inhibition. Therefore, P-32 is considered a powerful myelosuppressive agent. The indication to P-32 administration is true polycythemia, which, in contrast to secondary polycythemia accompanying numerous diseases, requires special cytostatic treatment. The study involved 152 patients with true polycythemia (76 men and 76 women aged 48) treated with P-32. The treatment was administered in case when bloodletting proved to be ineffective and hematocrit level exceeded 75%. P-32 was administered orally in 100 ml of 10% glucose solution on an empty stomach at a dose of 37-111 MBq with a 4-10-day intervals (mean 6 days). The blood count was checked for 12 weeks. If the number of thrombocytes and leukocytes decreased less than by 25% and the level of hematocrit did not normalize, repeated P-32 treatments were performed. In 13 (8.6%) patients, haematocrit parameters became normal after a single P-32 administration, in 15 (9.9%) patients two treatments with P-32 were necessary to normalize the blood count. In 134 (88.1%) cases P-32 treatment was administered more then two times (maximum 10 treatments). Total P-32 activity ranged from 37 to 740 MBq. Of all the patients who were administered P- 32 treatment, hematological

  6. The physical basis of biochemistry the foundations of molecular biophysics

    CERN Document Server

    Bergethon, Peter R

    1998-01-01

    The objective of this book is to provide a unifying approach to the study of biophysical chemistry for the advanced undergraduate who has had a year of physics, organic chem­ istry, calculus, and biology. This book began as a revised edition of Biophysical Chemistry: Molecules to Membranes, which Elizabeth Simons and I coauthored. That short volume was written in an attempt to provide a concise text for a one-semester course in biophysical chemistry at the graduate level. The experience of teaching biophysical chemistry to bi­ ologically oriented students over the last decade has made it clear that the subject requires a more fundamental text that unifies the many threads of modem science: physics, chem­ istry, biology, mathematics, and statistics. This book represents that effort. This volume is not a treatment of modem biophysical chemistry with its rich history and many contro­ versies, although a book on that topic is also needed. The Physical Basis of Biochemistry is an introduction to the philosophy...

  7. Radionuclide Sensors for Water Monitoring

    International Nuclear Information System (INIS)

    Grate, Jay W.; Egorov, Oleg B.; DeVol, Timothy A.

    2004-01-01

    Radionuclide contamination in the soil and groundwater at U.S. Department of Energy (DOE) sites is a severe problem that requires monitoring and remediation. Radionuclide measurement techniques are needed to monitor surface waters, groundwater, and process waters. Typically, water samples are collected and transported to an analytical laboratory, where costly radiochemical analyses are performed. To date, there has been very little development of selective radionuclide sensors for alpha- and beta-emitting radionuclides such as 90Sr, 99Tc, and various actinides of interest. The objective of this project is to investigate novel sensor concepts and materials for sensitive and selective determination of beta- and alpha-emitting radionuclide contaminants in water. To meet the requirements for loW--level, isotope-specific detection, the proposed sensors are based on radiometric detection. As a means to address the fundamental challenge of the short ranges of beta and alpha particle s in water, our overall approach is based on localization of preconcentration/separation chemistries directly on or within the active area of a radioactivity detector. Automated microfluidics is used for sample manipulation and sensor regeneration or renewal. The outcome of these investigations will be the knowledge necessary to choose appropriate chemistries for selective preconcentration of radionuclides from environmental samples, new materials that combine chemical selectivity with scintillating properties, new materials that add chemical selectivity to solid-state diode detectors, new preconcentrating column sensors, and improved instrumentation and signal processing for selective radionuclide sensors. New knowledge will provide the basis for designing effective probes and instrumentation for field and in situ measurements

  8. An ultra-sensitive biophysical risk assessment of light effect on skin cells.

    Science.gov (United States)

    Bennet, Devasier; Viswanath, Buddolla; Kim, Sanghyo; An, Jeong Ho

    2017-07-18

    The aim of this study was to analyze photo-dynamic and photo-pathology changes of different color light radiations on human adult skin cells. We used a real-time biophysical and biomechanics monitoring system for light-induced cellular changes in an in vitro model to find mechanisms of the initial and continuous degenerative process. Cells were exposed to intermittent, mild and intense (1-180 min) light with On/Off cycles, using blue, green, red and white light. Cellular ultra-structural changes, damages, and ECM impair function were evaluated by up/down-regulation of biophysical, biomechanical and biochemical properties. All cells exposed to different color light radiation showed significant changes in a time-dependent manner. Particularly, cell growth, stiffness, roughness, cytoskeletal integrity and ECM proteins of the human dermal fibroblasts-adult (HDF-a) cells showed highest alteration, followed by human epidermal keratinocytes-adult (HEK-a) cells and human epidermal melanocytes-adult (HEM-a) cells. Such changes might impede the normal cellular functions. Overall, the obtained results identify a new insight that may contribute to premature aging, and causes it to look aged in younger people. Moreover, these results advance our understanding of the different color light-induced degenerative process and help the development of new therapeutic strategies.

  9. Inverse problem in radionuclide transport

    International Nuclear Information System (INIS)

    Yu, C.

    1988-01-01

    The disposal of radioactive waste must comply with the performance objectives set forth in 10 CFR 61 for low-level waste (LLW) and 10 CFR 60 for high-level waste (HLW). To determine probable compliance, the proposed disposal system can be modeled to predict its performance. One of the difficulties encountered in such a study is modeling the migration of radionuclides through a complex geologic medium for the long term. Although many radionuclide transport models exist in the literature, the accuracy of the model prediction is highly dependent on the model parameters used. The problem of using known parameters in a radionuclide transport model to predict radionuclide concentrations is a direct problem (DP); whereas the reverse of DP, i.e., the parameter identification problem of determining model parameters from known radionuclide concentrations, is called the inverse problem (IP). In this study, a procedure to solve IP is tested, using the regression technique. Several nonlinear regression programs are examined, and the best one is recommended. 13 refs., 1 tab

  10. Radionuclide Retention in Concrete Wasteforms

    Energy Technology Data Exchange (ETDEWEB)

    Wellman, Dawn M.; Jansik, Danielle P.; Golovich, Elizabeth C.; Cordova, Elsa A.

    2012-09-24

    Assessing long-term performance of Category 3 waste cement grouts for radionuclide encasement requires knowledge of the radionuclide-cement interactions and mechanisms of retention (i.e., sorption or precipitation); the mechanism of contaminant release; the significance of contaminant release pathways; how wasteform performance is affected by the full range of environmental conditions within the disposal facility; the process of wasteform aging under conditions that are representative of processes occurring in response to changing environmental conditions within the disposal facility; the effect of wasteform aging on chemical, physical, and radiological properties; and the associated impact on contaminant release. This knowledge will enable accurate prediction of radionuclide fate when the wasteforms come in contact with groundwater. Data collected throughout the course of this work will be used to quantify the efficacy of concrete wasteforms, similar to those used in the disposal of LLW and MLLW, for the immobilization of key radionuclides (i.e., uranium, technetium, and iodine). Data collected will also be used to quantify the physical and chemical properties of the concrete affecting radionuclide retention.

  11. Radionuclide injury to the lung

    International Nuclear Information System (INIS)

    Dagle, G.E.; Sanders, C.L.

    1984-01-01

    Radionuclide injury to the lung has been studied in rats, hamsters, dogs, mice and baboons. Exposure of the lung to high dose levels of radionuclides produces a spectrum of progressively more severe functional and morphological changes, ranging from radiation pneumonitis and fibrosis to lung tumors. These changes are somewhat similar for different species. Their severity can be related to the absorbed radiation dose (measured in rads) produced by alpha, beta or gamma radiation emanating from various deposited radionuclides. The chemicophysical forms of radionuclides and spatial-temporal factors are also important variables. As with other forms of injury to the lung, repair attempts are highlighted by fibrosis and proliferation of pulmonary epithelium. Lung tumors are the principal late effect observed in experimental animals following pulmonary deposition of radionuclides at dose levels that do not result in early deaths from radiation pneumonitis or fibrosis. The predominant lung tumors described have been of epithelial origin and have been classified, in decreasing frequency of occurrence, as adenocarcinoma, bronchioloalveolar carcinoma, epidermoid carcinomas and combined epidermoid and adenocarcinoma. Mesothelioma and fibrosarcoma have been observed in rats, but less commonly in other species. Hemangiosarcomas were frequently observed in dogs exposed to beta-gamma emitters, and occasionally in rats exposed to alpha emitters. These morphologic changes in the lungs of experimental animals were reviewed and issues relevant to the prediction of human hazards discussed. 88 references

  12. 2. biophysical work meeting. Papers; 2. Biophysikalische Arbeitstagung; Vortraege

    Energy Technology Data Exchange (ETDEWEB)

    1992-11-01

    The report comprises 18 papers held at the 2nd Biophysical Work Meeting, 11 - 13 September 1991 in Schlema, Germany. The history of biophysics in Germany particularly of radiation biophysics and radon research, measurements of the radiation effects of radon and the derivation of limits, radon balneotherapy and consequences of uranium ore mining are dealt with. (orig.) [Deutsch] Der Report enthaelt 18 Vortraege, die auf der 2. Biophysikalischen Arbeitstagung in Schlema vom 11. bis 13. September 1991 gehalten wurden. Es werden die Geschichte der Biophysik in Deutschland, speziell der Strahlenbiophysik und Radonforschung, Messungen von Radon und seinen Folgeprodukten, Epidemiologie und Strahlenbiologie zur Bestimmung der Strahlenwirkung des Radons und die Ableitung entsprechender Grenzwerte, Radon-Balneotherapie und Folgen des Uranerzbergbaus behandelt. (orig.)

  13. Large-scale biophysical evaluation of protein PEGylation effects

    DEFF Research Database (Denmark)

    Vernet, Erik; Popa, Gina; Pozdnyakova, Irina

    2016-01-01

    PEGylation is the most widely used method to chemically modify protein biopharmaceuticals, but surprisingly limited public data is available on the biophysical effects of protein PEGylation. Here we report the first large-scale study, with site-specific mono-PEGylation of 15 different proteins...... of PEGylation on the thermal stability of a protein based on data generated by circular dichroism (CD), differential scanning calorimetry (DSC), or differential scanning fluorimetry (DSF). In addition, DSF was validated as a fast and inexpensive screening method for thermal unfolding studies of PEGylated...... proteins. Multivariate data analysis revealed clear trends in biophysical properties upon PEGylation for a subset of proteins, although no universal trends were found. Taken together, these findings are important in the consideration of biophysical methods and evaluation of second...

  14. Mesenchymal stem cells as therapeutic target of biophysical stimulation for the treatment of musculoskeletal disorders

    OpenAIRE

    Viganò, M; Sansone, V; D'Agostino, M; Romeo, P; Perucca Orfei, C; de Girolamo, L

    2016-01-01

    Background Musculoskeletal disorders are regarded as a major cause of worldwide morbidity and disability, and they result in huge costs for national health care systems. Traditional therapies frequently turned out to be poorly effective in treating bone, cartilage, and tendon disorders or joint degeneration. As a consequence, the development of novel biological therapies that can treat more effectively these conditions should be the highest priority in regenerative medicine. Main body of the ...

  15. Preface: Special Topic on Single-Molecule Biophysics.

    Science.gov (United States)

    Makarov, Dmitrii E; Schuler, Benjamin

    2018-03-28

    Single-molecule measurements are now almost routinely used to study biological systems and processes. The scope of this special topic emphasizes the physics side of single-molecule observations, with the goal of highlighting new developments in physical techniques as well as conceptual insights that single-molecule measurements bring to biophysics. This issue also comprises recent advances in theoretical physical models of single-molecule phenomena, interpretation of single-molecule signals, and fundamental areas of statistical mechanics that are related to single-molecule observations. A particular goal is to illustrate the increasing synergy between theory, simulation, and experiment in single-molecule biophysics.

  16. Institute of Biochemistry and Biophysics. Research Report 1996-1997

    International Nuclear Information System (INIS)

    1998-01-01

    Scientific interests of the Institute of Biochemistry and Biophysics of the Polish Academy of Sciences have evolved from classical biochemistry, biophysics and physiological chemistry to up-to-date molecular biology. Research interests are focussed on replication, mutagenesis and repair of DNA; regulation of gene expression at various levels; biosynthesis and post-translational modifications of proteins; gene sequencing and functional analysis of open reading frames; structure, function and regulation of enzymes; conformation of proteins and peptides; modelling of structures and prediction of functions of proteins; mechanisms of electron transfer in polypeptides

  17. [Biophysical methods in assessment of the skin microcirculation system].

    Science.gov (United States)

    Dynnik, O B; Mostovoĭ, S E; Berezovskiĭ, V A

    2008-01-01

    In this work has been analyzed the potential of biophysics methods in estimations of the microcirculatory system. Capillaroresistometry, Computer capillaroscopy and Laser Doppler Flowmetry can to detect of the endothelial dysfunction in the patients with chronic hepatic diseases. This instrumentals biophysics methods may be used in clinical investigations for screening early pathological conditions with dysfunction of the microcirculatory system. The methods Laser Doppler Flowmetry is important for investigations the patients with others diseases and for dynamical monitoring by quality of the treatment. The purpose of these methods an objective estimation of disorders in the microcirculatory system.

  18. Cell biology, biophysics, and mechanobiology: From the basics to Clinics.

    Science.gov (United States)

    Zeng, Y

    2017-04-29

    Cell biology, biomechanics and biophysics are the key subjects that guide our understanding in diverse areas of tissue growth, development, remodeling and homeostasis. Novel discoveries such as molecular mechanism, and mechanobiological mechanism in cell biology, biomechanics and biophysics play essential roles in our understanding of the pathogenesis of various human diseases, as well as in designing the treatment of these diseases. In addition, studies in these areas will also facilitate early diagnostics of human diseases, such as cardiovascular diseases and cancer. In this special issue, we collected 10 original research articles and 1 review...

  19. Institute of Biochemistry and Biophysics. Research Report 1996-1997

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-07-01

    Scientific interests of the Institute of Biochemistry and Biophysics of the Polish Academy of Sciences have evolved from classical biochemistry, biophysics and physiological chemistry to up-to-date molecular biology. Research interests are focussed on replication, mutagenesis and repair of DNA; regulation of gene expression at various levels; biosynthesis and post-translational modifications of proteins; gene sequencing and functional analysis of open reading frames; structure, function and regulation of enzymes; conformation of proteins and peptides; modelling of structures and prediction of functions of proteins; mechanisms of electron transfer in polypeptides.

  20. Exploring the biophysical properties of phytosterols in the plasma membrane for novel cancer prevention strategies.

    Science.gov (United States)

    Fakih, Omar; Sanver, Didem; Kane, David; Thorne, James L

    2018-05-03

    Cancer is a global problem with no sign that incidences are reducing. The great costs associated with curing cancer, through developing novel treatments and applying patented therapies, is an increasing burden to developed and developing nations alike. These financial and societal problems will be alleviated by research efforts into prevention, or treatments that utilise off-patent or repurposed agents. Phytosterols are natural components of the diet found in an array of seeds, nuts and vegetables and have been added to several consumer food products for the management of cardio-vascular disease through their ability to lower LDL-cholesterol levels. In this review, we provide a connected view between the fields of structural biophysics and cellular and molecular biology to evaluate the growing evidence that phytosterols impair oncogenic pathways in a range of cancer types. The current state of understanding of how phytosterols alter the biophysical properties of plasma membrane is described, and the potential for phytosterols to be repurposed from cardio-vascular to oncology therapeutics. Through an overview of the types of biophysical and molecular biology experiments that have been performed to date, this review informs the reader of the molecular and biophysical mechanisms through which phytosterols could have anti-cancer properties via their interactions with the plasma cell membrane. We also outline emerging and under-explored areas such as computational modelling, improved biomimetic membranes and ex vivo tissue evaluation. Focus of future research in these areas should improve understanding, not just of phytosterols in cancer cell biology but also to give insights into the interaction between the plasma membrane and the genome. These fields are increasingly providing meaningful biological and clinical data but iterative experiments between molecular biology assays, biosynthetic membrane studies and computational membrane modelling improve and refine our

  1. Method of preparing radionuclide doses

    International Nuclear Information System (INIS)

    Kuperus, J.H.

    1987-01-01

    A method is described of preparing aliquot dosea of a tracer material useful in diagnostic nuclear medicine comprising: storing discrete quantities of a lyophilized radionuclide carrier in separate tubular containers from which air and moisture is excluded, selecting from the tubular containers a container in which is stored a carrier appropriate for a nuclear diagnostic test to be performed, interposing the selected container between the needle and the barrel of a hypodermic syringe, and drawing a predetermined amount of a liquid containing a radionuclide tracer in known concentration into the hypodermic syringe barrel through the hypodermic needle and through the selected container to dissolve the discrete quantity of lyophilized carrier therein to combine the carrier with the radionuclide tracer to form an aliquot dose of nuclear diagnostic tracer material, as needed

  2. Methods of separating short half-life radionuclides from a mixture of radionuclides

    International Nuclear Information System (INIS)

    Bray, L.A.; Ryan, J.L.

    1998-01-01

    The present invention is a method of obtaining a radionuclide product selected from the group consisting of 223 Ra and 225 Ac, from a radionuclide ''cow'' of 227 Ac or 229 Th respectively. The method comprises the steps of (a) permitting ingrowth of at least one radionuclide daughter from said radionuclide ''cow'' forming an ingrown mixture; (b) insuring that the ingrown mixture is a nitric acid ingrown mixture; (c) passing the nitric acid ingrown mixture through a first nitrate form ion exchange column which permits separating the ''cow'' from at least one radionuclide daughter; (d) insuring that the at least one radionuclide daughter contains the radionuclide product; (e) passing the at least one radionuclide daughter through a second ion exchange column and separating the at least one radionuclide daughter from the radionuclide product and (f) recycling the at least one radionuclide daughter by adding it to the ''cow''. In one embodiment the radionuclide ''cow'' is the 227 Ac, the at least one daughter radionuclide is a 227 Th and the product radionuclide is the 223 Ra and the first nitrate form ion exchange column passes the 227 Ac and retains the 227 Th. In another embodiment the radionuclide ''cow'' is the 229 Th, the at least one daughter radionuclide is a 225 Ra and said product radionuclide is the 225 Ac and the 225 Ac and nitrate form ion exchange column retains the 229 Th and passes the 225 Ra/Ac. 8 figs

  3. Therapeutic ultrasound

    International Nuclear Information System (INIS)

    Crum, Lawrence A

    2004-01-01

    The use of ultrasound in medicine is now quite commonplace, especially with the recent introduction of small, portable and relatively inexpensive, hand-held diagnostic imaging devices. Moreover, ultrasound has expanded beyond the imaging realm, with methods and applications extending to novel therapeutic and surgical uses. These applications broadly include: tissue ablation, acoustocautery, lipoplasty, site-specific and ultrasound mediated drug activity, extracorporeal lithotripsy, and the enhancement of natural physiological functions such as wound healing and tissue regeneration. A particularly attractive aspect of this technology is that diagnostic and therapeutic systems can be combined to produce totally non-invasive, imageguided therapy. This general lecture will review a number of these exciting new applications of ultrasound and address some of the basic scientific questions and future challenges in developing these methods and technologies for general use in our society. We shall particularly emphasize the use of High Intensity Focused Ultrasound (HIFU) in the treatment of benign and malignant tumors as well as the introduction of acoustic hemostasis, especially in organs which are difficult to treat using conventional medical and surgical techniques. (amum lecture)

  4. Chemical and Biophysical Modulation of Cas9 for Tunable Genome Engineering.

    Science.gov (United States)

    Nuñez, James K; Harrington, Lucas B; Doudna, Jennifer A

    2016-03-18

    The application of the CRISPR-Cas9 system for genome engineering has revolutionized the ability to interrogate genomes of mammalian cells. Programming the Cas9 endonuclease to induce DNA breaks at specified sites is achieved by simply modifying the sequence of its cognate guide RNA. Although Cas9-mediated genome editing has been shown to be highly specific, cleavage events at off-target sites have also been reported. Minimizing, and eventually abolishing, unwanted off-target cleavage remains a major goal of the CRISPR-Cas9 technology before its implementation for therapeutic use. Recent efforts have turned to chemical biology and biophysical approaches to engineer inducible genome editing systems for controlling Cas9 activity at the transcriptional and protein levels. Here, we review recent advancements to modulate Cas9-mediated genome editing by engineering split-Cas9 constructs, inteins, small molecules, protein-based dimerizing domains, and light-inducible systems.

  5. Modern nuclear medicine methods as a topic of biophysics in veterinary training at UVM in Kosice

    International Nuclear Information System (INIS)

    Stanicova, J.; Lohajova, L.

    2004-01-01

    Diagnostic and therapeutic application of ionising radiation is very important in all of branches of medicine including veterinary medicine. In veterinary training at University of Veterinary Medicine in Kosice (UVM), biophysics is a basic subject and it grants physical basis necessary for understanding subsequent subjects such as veterinary surgery, roentgenology, orthopedics. In view of this, traditional methods of radiology such as fluoroscopy, skiagraphy and tomography are explaining. The appearance and application of the theory so called reconstruction of image and also computers led to qualitatively new solutions via the development of modern methods in radiology. Explaining of physical principles, advantages or disadvantages of these new methods is also important in veterinary training although some of them do not use in veterinary practice yet. Two modern methods of nuclear medicine using in diagnostic (SPECT and PET) are discussed bellow. (authors)

  6. Biophysical Stimuli: A Review of Electrical and Mechanical Stimulation in Hyaline Cartilage.

    Science.gov (United States)

    Vaca-González, Juan J; Guevara, Johana M; Moncayo, Miguel A; Castro-Abril, Hector; Hata, Yoshie; Garzón-Alvarado, Diego A

    2017-09-01

    Objective Hyaline cartilage degenerative pathologies induce morphologic and biomechanical changes resulting in cartilage tissue damage. In pursuit of therapeutic options, electrical and mechanical stimulation have been proposed for improving tissue engineering approaches for cartilage repair. The purpose of this review was to highlight the effect of electrical stimulation and mechanical stimuli in chondrocyte behavior. Design Different information sources and the MEDLINE database were systematically revised to summarize the different contributions for the past 40 years. Results It has been shown that electric stimulation may increase cell proliferation and stimulate the synthesis of molecules associated with the extracellular matrix of the articular cartilage, such as collagen type II, aggrecan and glycosaminoglycans, while mechanical loads trigger anabolic and catabolic responses in chondrocytes. Conclusion The biophysical stimuli can increase cell proliferation and stimulate molecules associated with hyaline cartilage extracellular matrix maintenance.

  7. Producing new radionuclides for medicine

    International Nuclear Information System (INIS)

    Michaut, C.

    2009-01-01

    The Arronax cyclotron, a new particle accelerator dedicated to the production of radionuclides for medicine and research has been commissioned in Nantes (France). Because of its unique features: an energy of 70 MeV and an intensity of 750 μA, Arronax will produce radionuclides that can not be produce in present cyclotrons. Among others it will produce Strontium-82 and Germanium-68 that are the precursors for Rubidium-82 and Gallium-68 respectively. 20 per cent of the research works will be dedicated to other domains like radioactive wastes, the radiation biological damage and the radiation damage on electronic devices. (A.C.)

  8. Radionuclide migration in geological formations

    International Nuclear Information System (INIS)

    Barbreau, A.; Heremans, R.; Skytte Jensen, B.

    1980-01-01

    Radioactive waste disposal into geological formation is based on the capacity of rocks to confine radioactivity for a long period of time. Radionuclide migration from the repository to the environment depends on different mechanisms and phenomena whose two main ones are groundwater flow and the retention and ion-exchange property of rocks. Many studies are underway presently in EEC countries concerning hydrodynamic characteristics of deep geological formations as well as in radionuclide retention capacity and modelling. Important results have already been achieved which show the complexity of some phenomena and further studies shall principally be developed taking into account real conditions of the repository and its environment

  9. Automatic alignment of radionuclide images

    International Nuclear Information System (INIS)

    Barber, D.C.

    1982-01-01

    The variability of the position, dimensions and orientation of a radionuclide image within the field of view of a gamma camera hampers attempts to analyse the image numerically. This paper describes a method of using a set of training images of a particular type, in this case right lateral brain images, to define the likely variations in the position, dimensions and orientation for that type of image and to provide alignment data for a program that automatically aligns new images of the specified type to a standard position, size and orientation. Examples are given of the use of this method on three types of radionuclide image. (author)

  10. Radionuclide techniques for brain imaging

    International Nuclear Information System (INIS)

    Cowan, R.J.; Moody, D.M.

    1984-01-01

    Over the past decade, many of the prime indications for radionuclide brain scanning have become instead indications for CCT, and nuclear medicine studies of the brain have assumed more of a complementary, supportive role. However, there is great promise for improvement in central nervous system radionuclide applications with advances anticipated in both radiopharmaceuticals and instrumentation. Nuclear medicine is continuing to function as a powerful research tool and, in the relatively near future, may regain its role as a major clinical test of the central nervous system

  11. Reactor-produced therapeutic radioisotopes

    International Nuclear Information System (INIS)

    Knapp, F.F. Jr.

    2002-01-01

    The significant worldwide increase in therapeutic radioisotope applications in nuclear medicine, oncology and interventional cardiology requires the dependable production of sufficient levels of radioisotopes for these applications (Reba, 2000; J. Nucl. Med., 1998; Nuclear News, 1999; Adelstein and Manning, 1994). The issues associated with both accelerator- and reactor-production of therapeutic radioisotopes is important. Clinical applications of therapeutic radioisotopes include the use of both sealed sources and unsealed radiopharmaceutical sources. Targeted radiopharmaceutical agents include those for cancer therapy and palliation of bone pain from metastatic disease, ablation of bone marrow prior to stem cell transplantation, treatment modalities for mono and oligo- and polyarthritis, for cancer therapy (including brachytherapy) and for the inhibition of the hyperplastic response following coronary angioplasty and other interventional procedures (For example, see Volkert and Hoffman, 1999). Sealed sources involve the use of radiolabeled devices for cancer therapy (brachytherapy) and also for the inhibition of the hyperplasia which is often encountered after angioplasty, especially with the exponential increase in the use of coronary stents and stents for the peripheral vasculature and other anatomical applications. Since neutron-rich radioisotopes often decay by beta decay or decay to beta-emitting daughter radioisotopes which serve as the basis for radionuclide generator systems, reactors are expected to play an increasingly important role for the production of a large variety of therapeutic radioisotopes required for these and other developing therapeutic applications. Because of the importance of the availability of reactor-produced radioisotopes for these applications, an understanding of the contribution of neutron spectra for radioisotope production and determination of those cross sections which have not yet been established is important. This

  12. Applications of extraction chromatography in the development of radionuclide generator systems for nuclear medicine

    International Nuclear Information System (INIS)

    Dietz, M.L.; Horwitz, E.P.

    2000-01-01

    Numerous methods have been described for the separation and purification of radionuclides for application in diagnostic and therapeutic nuclear medicine, among them ion exchange, solvent extraction, and various forms of chromatography. Although extraction chromatography has previously been shown to provide a means of performing a number of separations of potential use in radionuclide generator systems, the application of the technique to generator development has thus far been limited. Recent work directed at improved methods for the determination of radionuclides in biological and environmental samples has led to the development of a series of novel extraction chromatographic resins exhibiting enhanced metal ion retention from strongly acidic media and excellent selectivity, among them materials suitable for the isolation of 212 Bi, 90 Y, and 213 Bi. These resins, along with extraction chromatographic materials employing functionalized supports to improve their physical stability or metal ion retention properties, are shown to offer promise in the development of improved radionuclide generators

  13. Determination of alpha radionuclides in fish

    International Nuclear Information System (INIS)

    Pernicka, L.; Matel, L.; Rosskopfova, O.

    2001-01-01

    In atmospheric water, external water and undercurrent the occurrence of radionuclides is usual. It is an important factor of quality of the environment. Plants ingest radionuclides from water and with they everyone. And it arises radioactivity infest food-chain. Radiotoxicity of this radionuclides is very deer sometimes. The sensitive radiochemical procedures for their determination are necessarily important. The poster presents the combined procedure used at our laboratory for determination of alpha radionuclides in biological samples. (authors)

  14. Biophysical constraints on leaf expansion in a tall conifer.

    Science.gov (United States)

    Fredrick C. Meinzer; Barbara J. Bond; Jennifer A. Karanian

    2008-01-01

    The physiological mechanisms responsible for reduced extension growth as trees increase in height remain elusive. We evaluated biophysical constraints on leaf expansion in old-growth Douglas-fir (Psuedotsuga menziesii (Mirb.) Franco) trees. Needle elongation rates, plastic and elastic extensibility, bulk leaf water, (L...

  15. Seminal Fluid Analysis And Biophysical Profile: Findings And ...

    African Journals Online (AJOL)

    Seminal Fluid Analysis And Biophysical Profile: Findings And Relevance In Infertile Males In Ilorin, Nigeria. EK Oghagbon, AAG Jimoh, SA Adebisi. Abstract. To determine if there was a bearing of body mass index (BMI) on male infertility, a cross-sectional study of males of infertile couples, attending our infertility clinic was ...

  16. Delineating Biophysical Environments of the Sunda Banda Seascape, Indonesia

    Directory of Open Access Journals (Sweden)

    Mingshu Wang

    2015-01-01

    Full Text Available The Sunda Banda Seascape (SBS, located in the center of the Coral Triangle, is a global center of marine biodiversity and a conservation priority. We proposed the first biophysical environmental delineation of the SBS using globally available satellite remote sensing and model-assimilated data to categorize this area into unique and meaningful biophysical classes. Specifically, the SBS was partitioned into eight biophysical classes characterized by similar sea surface temperature, chlorophyll a concentration, currents, and salinity patterns. Areas within each class were expected to have similar habitat types and ecosystem functions. Our work supplemented prevailing global marine management schemes by focusing in on a regional scale with finer spatial resolution. It also provided a baseline for academic research, ecological assessments and will facilitate marine spatial planning and conservation activities in the area. In addition, the framework and methods of delineating biophysical environments we presented can be expanded throughout the whole Coral Triangle to support research and conservation activities in this important region.

  17. Perspectives and Plans for Graduate Studies. 16. Biophysics 1974.

    Science.gov (United States)

    Ontario Council on Graduate Studies, Toronto. Advisory Committee on Academic Planning.

    In March, 1973, after a review of the Ontario universities' three-year plans, a provisional embargo was placed on doctoral work in biophysics. A full-scale assessment with outside consultants was not necessary in the case of a provisional embargo. Instead, the method used to remove the embargo was self-study by the discipline group leading to a…

  18. Southwest Ecological Restoration Institutes (SWERI) Biophysical Monitoring Workshop Report

    Science.gov (United States)

    Joseph Seidenberg; Judy Springer; Tessa Nicolet; Mike Battaglia; Christina Vothja

    2009-01-01

    On October 15-16, 2009, the Southwest Ecological Restoration Institutes (SWERI) hosted a workshop in which the participants would 1) build a common understanding of the types of monitoring that are occurring in forested ecosystems of the Southwest; 2) analyze and agree on an efficient, yet robust set of biophysical variables that can be used by land mangers and...

  19. Dosimetry techniques for applications of incorporated radionuclides

    International Nuclear Information System (INIS)

    Howell, R.W.; Rao, D.V.; Haydock, C.

    1989-01-01

    Beta particle emitters are attracting attention as the radiolabels of choice for therapeutic radiopharmaceutical. Their use in cancer therapy has drawn attention to a variety of problems in estimating the absorbed dose to primary tumors and metastases from incorporated Β-emitters. Experimental evidence indicates that the distribution of radiopharmaceutical, such as radiolabeled monoclonal antibodies, is highly nonuniform in tumor tissue. Three levels of nonuniformity may be noted: (1) inhomogeneity at the macroscopic level due to poor penetration of the radiopharmaceutical into the tumor, (2) microscopic inhomogeneity due to large variations in the number of binding sites on the tumor cells, and (3) nonuniformity at the subcellular level. Conventional application of the MIRD Schema for calculating absorbed doses from incorporated radionuclides may be inadequate under these circumstances since this approach assumes that the, distribution of radioactivity in the organ is uniform. The conventional dosimetry may be modified to handle inhomogeneous activity distributions by dividing the tumor into a number of subregions. At the macroscopic level a spherical tumor may be broken up into a group of concentric annular regions of tissue. At the microscopic level the tumor or metastasis may be considered as a multicellular cluster which in essence divides the tumor into many subtumors of cellular dimensions. Finally, at the subcellular level, a cancer cell may be viewed as consisting of several compartments: the cell membrane, cytoplasm, and nucleus. In each case absorbed fractions, and therefore the total absorbed doses, may be calculated for the various subregions of the tumor using standard MIRD procedures. Using macroscopic and multicellular dosimetry models, the relative importance of these various levels of inhomogeneity in radionuclide distribution is examined. A dosimetry model which accounts for the possible time dependence of the tumor mass is formulated

  20. Peptide Receptor Radionuclide Therapy with (90)Y-DOTATOC and (177)Lu-DOTATOC in Advanced Neuroendocrine Tumors: Results from a Danish Cohort Treated in Switzerland

    DEFF Research Database (Denmark)

    Pfeifer, Andreas Klaus; Gregersen, Tine; Grønbæk, Henning

    2011-01-01

    Limited therapeutic options have highlighted the demand for new treatment modalities for patients with advanced neuroendocrine tumors (NET). Promising results of initial studies have warranted the implementation of peptide receptor radionuclide therapy (PRRT) in clinical practice. However, this t...

  1. Peptide receptor radionuclide therapy with Y-DOTATOC and (177)Lu-DOTATOC in advanced neuroendocrine tumors: results from a Danish cohort treated in Switzerland

    DEFF Research Database (Denmark)

    Pfeifer, Andreas Klaus; Gregersen, Tine; Grønbæk, Henning

    2011-01-01

    Limited therapeutic options have highlighted the demand for new treatment modalities for patients with advanced neuroendocrine tumors (NET). Promising results of initial studies have warranted the implementation of peptide receptor radionuclide therapy (PRRT) in clinical practice. However, this t...

  2. Naturally occurring radionuclides in food

    International Nuclear Information System (INIS)

    Djujic, I.

    1995-01-01

    The naturally occurring radionuclides are the major source of radiation exposure to humans. The principal way of natural radiation exposure is the inhalation of 222 Rn decay products (about 85% of the total). The remainder is equally divided between internally deposited radionuclides, cosmic and terrestrial sources. In the present study, the content of 40 K, 210 Pb, 226 Ra, 230 Th, 232 Th and 238 U in representative food samples (milk, pork, beef, potatoes, wheat and corn flour) and samples of different food items that do not represent entire national production but provide interesting additional data for approximative calculation of naturally occurring radionuclide intake is presented. Daily weight of food eaten, participation of food groups, as well as daily intake by food of mentioned naturally occurring radionuclides in the Serbian diet was obtained on the base of house hold budget surveys. The result obtained for daily intake estimates in mBq for Serbian population are 78.1 ( 40 K), 38.2( 210 Pb), 52.3( 226 Ra), 2.0( 230 Th) and 12.5( 238 U). (author)

  3. 100 Years of radionuclide metrology

    International Nuclear Information System (INIS)

    Judge, S.M.; Arnold, D.; Chauvenet, B.; Collé, R.; De Felice, P.; García-Toraño, E.; Wätjen, U.

    2014-01-01

    The discipline of radionuclide metrology at national standards institutes started in 1913 with the certification by Curie, Rutherford and Meyer of the first primary standards of radium. In early years, radium was a valuable commodity and the aim of the standards was largely to facilitate trade. The focus later changed to providing standards for the new wide range of radionuclides, so that radioactivity could be used for healthcare and industrial applications while minimising the risk to patients, workers and the environment. National measurement institutes responded to the changing demands by developing new techniques for realising primary standards of radioactivity. Looking ahead, there are likely to be demands for standards for new radionuclides used in nuclear medicine, an expansion of the scope of the field into quantitative imaging to facilitate accurate patient dosimetry for nuclear medicine, and an increasing need for accurate standards for radioactive waste management and nuclear forensics. - Highlights: • The driving forces for the development of radionuclide metrology. • Radium standards to facilitate trade of this valuable commodity in the early years. • After 1950, focus changes to healthcare and industrial applications. • National Measurement Institutes develop new techniques, standards, and disseminate the best practice in measurement. • Challenges in nuclear medicine, radioactive waste management and nuclear forensics

  4. Chemistry and analysis of radionuclides

    CERN Document Server

    Lehto, Jukka

    2010-01-01

    Written by chemists for chemists, this is a comprehensive guide to the important radionuclides as well as techniques for their separation and analysis. It introduces readers to the important laboratory techniques and methodologies in the field, providing practical instructions on how to handle nuclear waste and radioactivity in the environment.

  5. Radionuclide migration studies in soil

    International Nuclear Information System (INIS)

    Marumo, J.T.

    1989-01-01

    In this work a brief description about retention and migration parameters of radionuclides in soil, including main methods to determine the distribution coefficient (K) are given. Some of several factors that can act on the migration are also mentioned. (author) [pt

  6. Measurement of radionuclides in waste packages

    Science.gov (United States)

    Brodzinski, R.L.; Perkins, R.W.; Rieck, H.G.; Wogman, N.A.

    1984-09-12

    A method is described for non-destructively assaying the radionuclide content of solid waste in a sealed container by analysis of the waste's gamma-ray spectrum and neutron emissions. Some radionuclides are measured by characteristic photopeaks in the gamma-ray spectrum; transuranic nuclides are measured by neutron emission rate; other radionuclides are measured by correlation with those already measured.

  7. Performance and quality control of radionuclide calibrators in nuclear medicine

    International Nuclear Information System (INIS)

    Woods, M.J.; Baker, M.

    2002-01-01

    Full text: The use of ionising radiations in nuclear medicine has traditionally divided itself into two specific areas. The diagnostic usage has generally been dominated by the injection or ingestion of radionuclides. The therapeutic applications, on the other hand, have usually been accomplished by the application of ionising radiation, both from machines and radionuclide sources, whereby the radiation source is external to the patient. Over recent years, this divide has become increasingly blurred and the science between diagnosis and therapy has become significantly closer. This is particularly the situation in respect of the instruments used to determine the activity or dose delivered by the radiation source. In the ideal therapeutic situation, the radiation dose would be delivered solely to the malignant tissue. With external radiation therapy, this can never be achieved completely but this ideal can be approached more closely with targeted radiotherapy wherein radionuclides are introduced directly into the malignancy either as a solid, physical source or as a solution that, by its chemistry, concentrates into the area of interest. In order to achieve the optimum efficacy of treatment, there is an associated requirement to determine accurately the activity or dose rate of the radioactive source being used. It is here that the technology used in the diagnostic field can also be used to advantage for therapeutic applications. For diagnosis, the instrument of choice is the radionuclide calibrator and this equipment is increasingly finding parallel usage for the characterisation of therapeutic sources. Despite their appearances however, radionuclide calibrators are not 'black boxes' and need to be used with care, subjected to a robust level of quality control and operated by personnel who have a fundamental understanding of their operational characteristics. A measure of the level of performance of operational radionuclide calibrators and the competence of their

  8. Polish Academy of Sciences Institute of Biochemistry and Biophysics research report 1994-1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-31

    Scientific interests of Institute of Biochemistry and Biophysics Polish Academy of Sciences are focused on DNA replication and repair, gene expression, gene sequencing and molecular biophysics. The work reviews research projects of the Institute in 1994-1995.

  9. Polish Academy of Sciences Institute of Biochemistry and Biophysics research report 1994-1995

    International Nuclear Information System (INIS)

    1996-01-01

    Scientific interests of Institute of Biochemistry and Biophysics Polish Academy of Sciences are focused on DNA replication and repair, gene expression, gene sequencing and molecular biophysics. The work reviews research projects of the Institute in 1994-1995

  10. Polish Academy of Sciences Institute of Biochemistry and Biophysics research report 1994-1995

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-31

    Scientific interests of Institute of Biochemistry and Biophysics Polish Academy of Sciences are focused on DNA replication and repair, gene expression, gene sequencing and molecular biophysics. The work reviews research projects of the Institute in 1994-1995.

  11. Surface-enhanced Raman scattering: a new optical probe in molecular biophysics and biomedicine

    DEFF Research Database (Denmark)

    Kneipp, J.; Wittig, B.; Bohr, Henrik

    2010-01-01

    Sensitive and detailed molecular structural information plays an increasing role in molecular biophysics and molecular medicine. Therefore, vibrational spectroscopic techniques, such as Raman scattering, which provide high structural information content are of growing interest in biophysical and ...

  12. Status report on radionuclide transfer

    International Nuclear Information System (INIS)

    1980-01-01

    At the suggestion of the Federal Minstry of the Interior, in June 1978, a group of scientists from several institutions who are active in the field of radionuclide transfer or are interested in these problems got together. During the discussions of the work team, especially the transfer soil/plants was emphasized. Then the work team set up a status report on the transfer of the radionuclides relevant in the sense of the radiation protection act. The nuclides H 3 and C14, the isotopes of the Sr, J, and Cs, Tc99, the so-called corrosion nuclides Mn54, Fe59, co-isotopes and Zn65, and isotopes of Pu, Am, and Cm were regarded as important for a possible radiation exposition. Recent investigations revealed that also the natural radionuclides Ra226, Po210, and Pb210 should be covered by the investigations. The goal of this status report is to present the level of knowledge on the transfer of these radionuclides to man in a brief form, giving hints at the most important literature. It was requested by the Federal Ministry of the Interior, as fas as possible, to indicate transfer factors which are necessary for the radio-occology act to be decreed according to Para. 45 of the radiation protection act. Another goal of the report was to show the gap in the knowledge on the radio nuclide transfer. This was thought to help to create a basis for the decisions of the Federal Ministry concerning the support of other investigation projects in the field of transfer of radionuclides. (orig./MG) [de

  13. Dosimetric characterization of radionuclides for systemic tumor therapy: Influence of particle range, photon emission, and subcellular distribution

    International Nuclear Information System (INIS)

    Uusijaervi, Helena; Bernhardt, Peter; Ericsson, Thomas; Forssell-Aronsson, Eva

    2006-01-01

    emitters, photon emitters, and alpha emitters. The TND values of the beta emitters were not affected by the subcellular distribution of the radionuclide. The TND values of the Auger electron emitters were affected by the subcellular radionuclide distribution. The photon emitters showed low TND values that were only slightly affected by the subcellular radionuclide distribution. The alpha emitters showed high TND values that were only slightly affected by the subcellular radionuclide distribution. This dosimetric characterization of radionuclides may be valuable in choosing the appropriate radionuclides for specific therapeutic applications

  14. Conditions and processes affecting radionuclide transport

    Science.gov (United States)

    Simmons, Ardyth M.; Neymark, Leonid A.

    2012-01-01

    Characteristics of host rocks, secondary minerals, and fluids would affect the transport of radionuclides from a previously proposed repository at Yucca Mountain, Nevada. Minerals in the Yucca Mountain tuffs that are important for retarding radionuclides include clinoptilolite and mordenite (zeolites), clay minerals, and iron and manganese oxides and hydroxides. Water compositions along flow paths beneath Yucca Mountain are controlled by dissolution reactions, silica and calcite precipitation, and ion-exchange reactions. Radionuclide concentrations along flow paths from a repository could be limited by (1) low waste-form dissolution rates, (2) low radionuclide solubility, and (3) radionuclide sorption onto geological media.

  15. Radionuclide transfer from mother to embryo

    International Nuclear Information System (INIS)

    Toader, M.; Vasilache, R.A.; Scridon, R.; Toader, M.L.

    1998-01-01

    The transfer of radionuclides from mother to embryo is still a matter of high interest. Therefore, the relation was investigated between the amount of radionuclides in the embryo and the dietary intake of the mother, this for two scenarios: a recurrent intake of variable amounts of radionuclides, and a long-term intake of a relatively constant amount of radionuclides, the radionuclide being 137 Cs. In the first case, the amount of radionuclides present in the embryo increases with the age of the embryo and with the intake of the mother. In the second case, no correlation could be found between the age of the embryo and its radioactive content; only the correlation between the intake of the mother and the radionuclide content of the embryo remained. (A.K.)

  16. Sequential radionuclide bone imaging in avascular pediatric hip conditions

    International Nuclear Information System (INIS)

    Minikel, J.; Sty, J.; Simons, G.

    1983-01-01

    Radionuclide bone imaging was performed on six patients with various hip conditions. Initial bone images revealed diminished uptake of isotope /sup 99m/Tc-MDP in the capital femoral epiphysis. Following therapeutic intervention, repeat bone scans revealed normal uptake of /sup 99m/Tc-MDP in the capital femoral epiphysis. Subsequent radiographs revealed that avascular necrosis had not occurred. There are two types of avascularity: the potentially reversible, and the irreversible. Attempts should be made toward early recognition of the potentially reversible avascular insult. With early recognition, surgical reconstruction prior to osteophyte death may result in revascularization. If this can be accomplished, avascular necrosis can be avoided

  17. Radionuclide assessment of vascular complications in renal transplant patients

    International Nuclear Information System (INIS)

    Chanard, J.; Clavel, P.; Loboguerreros, A.; Toupance, O.; Lepailleur, A.; Brandt, B.; Liehn, J.C.

    1994-01-01

    Nuclear medicine can make an efficient contribution to the diagnosis and monitoring of renal disease and to the assessment of therapeutic interventions in the field of renal transplantation. The new radio pharmaceutical MAG 3 labelled with 99m Tc provides renal imaging of quality in patients with impaired renal function and enables quantitative evaluation of renal function. We report on radionuclide evaluation, with special emphasis on the analysis of the vascular component of the scintigram, in the different clinical situations (i.e. renal failure) that may compromise the outcome of a successful renal transplant. (authors)

  18. Guidelines for Rational Cancer Therapeutics

    Directory of Open Access Journals (Sweden)

    Byunghee Yoo

    2017-12-01

    Full Text Available Traditionally, cancer therapy has relied on surgery, radiation therapy, and chemotherapy. In recent years, these interventions have become increasingly replaced or complemented by more targeted approaches that are informed by a deeper understanding of the underlying biology. Still, the implementation of fully rational patient-specific drug design appears to be years away. Here, we present a vision of rational drug design for cancer that is defined by two major components: modularity and image guidance. We suggest that modularity can be achieved by combining a nanocarrier and an oligonucleotide component into the therapeutic. Image guidance can be incorporated into the nanocarrier component by labeling with a specific imaging reporter, such as a radionuclide or contrast agent for magnetic resonance imaging. While limited by the need for additional technological advancement in the areas of cancer biology, nanotechnology, and imaging, this vision for the future of cancer therapy can be used as a guide to future research endeavors.

  19. Radionuclide behavior at underground environment

    International Nuclear Information System (INIS)

    Hahn, Phil Soo; Park, Chung Kyun; Keum, Dong Kwon; Cho, Young Hwan; Kang, Moon Ja; Baik, Min Hoon; Hahn, Kyung Won; Chun, Kwan Sik; Park, Hyun Soo

    2000-03-01

    This study of radionuclide behavior at underground environment has been carried out as a part of the study of high-level waste disposal technology development. Therefore, the main objectives of this project are constructing a data-base and producing data for the safety assessment of a high-level radioactive waste, and verification of the objectivity of the assessment through characterization of the geochemical processes and experimental validation of the radionuclide migration. The various results from the this project can be applicable to the preliminary safety and performance assessments of the established disposal concept for a future high-level radioactive waste repository. Providing required data and technical basis for assessment methodologies could be a direct application of the results. In a long-term view, the results can also be utilized as a technical background for the establishment of government policy for high-level radioactive waste disposal

  20. Choice of radionuclides for radioimmunotherapy

    International Nuclear Information System (INIS)

    DeNardo, S.J.; Jungerman, J.A.; DeNardo, G.L.; Lagunas-Solar, M.C.; Cole, W.C.; Meares, C.F.

    1985-01-01

    Innumerable questions need to be answered and obstacles overcome before radioimmunotherapy can be generally successful in cancer patients. Major developments have greatly enhanced the likelihood of success. The important development of appropriate radionuclides and radiochemistry for this therapy must be intimately linked with the biological and biochemical realities. All aspects must be considered, such as the specific nature of the antigenic target, the pharmacokinetics of the antibody fragment carrier, the capability of in vivo quantitation of tumor uptake and turnover time, as well as total body kinetics. With this knowledge, then, practical radiochemistry methods can be integrated with the suitable radionuclide choices, and production methods can be developed which will deliver effective and dependable products for patient therapy

  1. Radionuclide transfer in terrestrial animals

    International Nuclear Information System (INIS)

    DiGregorio, D.; Kitchings, T.; Van Voris, P.

    1978-01-01

    The analysis of dispersion of radionuclides in terrestrial food chains, generally, is a series of equations identifying the fractional input and outflow rates from trophic level to trophic level. Data that are prerequisite inputs for these food chain transport models include: (1) identification of specific transport pathway, (2) assimilation at each pathway link, and (3) the turnover rate or retention function by successive receptor species in the appropriate food chain. In this report, assimilation coefficients, biological half-lives, and excretion rates for a wide variety of vertebrate and invertebrate species and radionuclides have been compiled from an extensive search of the available literature. Using the information accumulated from the literature, correlations of nuclide metabolism and body weight are also discussed. (author)

  2. Applications of radionuclides in industry

    International Nuclear Information System (INIS)

    Leveque, P.

    1955-01-01

    After a brief recall of a few concepts (mass number, charge and beams properties) and the description of used detectors (ionization chamber, Geiger-Mueller counter, scintillation counters), some radionuclides applications are described. In a first part, the well-developed applications are presented in three distinct groups: continuous applications such as β and γ gauges (determination hydrogen content of an hydrocarbon and content of an emulsion; discharge of static electricity), discontinuous applications such as radiography and autoradiography, wear or manufacture problems (distribution of a fungicide on tobacco) and finally, applications in research laboratories such as diffusion, exchange and solubility. It also describes the applications which are still in development such as the action of beams on matter (reticulation and degradation of polymers, monomers polymerisation, cold sterilization). In conclusion, few advices on the opportunity of such applications and the choice of the radionuclides are given. (M.P.)

  3. Radionuclide imaging of musculoskeletal infection

    International Nuclear Information System (INIS)

    Palestr, Christopher J.; North Shore Long Island Jewish Health System, Manhasset and New Hyde Park, NY; Love, Charito

    2007-01-01

    Radionuclide imaging studies are routinely used to evaluate patients suspected of having musculoskeletal infection. Three-phase bone imaging is readily available, relatively inexpensive, and very accurate in the setting of otherwise normal bone. Labeled leukocyte imaging should be used in cases of 'complicating osteomyelitis' such as prosthetic joint infection. This test also is useful in clinically unsuspected diabetic pedal osteomyelitis as well as in the neuropathic joint. It is often necessary, however, to perform complementary bone marrow imaging, to maximize the accuracy of labeled leukocyte imaging. In contrast to other regions in the skeleton, labeled leukocyte imaging is not useful for diagnosing spinal osteomyelitis. At the moment, gallium is the preferred radionuclide procedure for this condition and is a useful adjunct to magnetic resonance imaging. FDG-PET likely will play an important role in the evaluation of musculoskeletal infection, especially spinal osteomyelitis, and may replace gallium imaging for this purpose. (author)

  4. Radionuclide behavior at underground environment

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, Phil Soo; Park, Chung Kyun; Keum, Dong Kwon; Cho, Young Hwan; Kang, Moon Ja; Baik, Min Hoon; Hahn, Kyung Won; Chun, Kwan Sik; Park, Hyun Soo

    2000-03-01

    This study of radionuclide behavior at underground environment has been carried out as a part of the study of high-level waste disposal technology development. Therefore, the main objectives of this project are constructing a data-base and producing data for the safety assessment of a high-level radioactive waste, and verification of the objectivity of the assessment through characterization of the geochemical processes and experimental validation of the radionuclide migration. The various results from the this project can be applicable to the preliminary safety and performance assessments of the established disposal concept for a future high-level radioactive waste repository. Providing required data and technical basis for assessment methodologies could be a direct application of the results. In a long-term view, the results can also be utilized as a technical background for the establishment of government policy for high-level radioactive waste disposal.

  5. Radionuclide imaging of musculoskeletal infection

    Energy Technology Data Exchange (ETDEWEB)

    Palestr, Christopher J. [Albert Einstein College of Medicine, Bronx, NY (United States); North Shore Long Island Jewish Health System, Manhasset and New Hyde Park, NY (United States). Div. of Nuclear Medicine and Molecular Imaging; E-mail: palestro@lij.edu; Love, Charito [North Shore Long Island Jewish Health System, Manhasset and New Hyde Park, NY (United States). Div. of Nuclear Medicine and Molecular Imaging

    2007-09-15

    Radionuclide imaging studies are routinely used to evaluate patients suspected of having musculoskeletal infection. Three-phase bone imaging is readily available, relatively inexpensive, and very accurate in the setting of otherwise normal bone. Labeled leukocyte imaging should be used in cases of 'complicating osteomyelitis' such as prosthetic joint infection. This test also is useful in clinically unsuspected diabetic pedal osteomyelitis as well as in the neuropathic joint. It is often necessary, however, to perform complementary bone marrow imaging, to maximize the accuracy of labeled leukocyte imaging. In contrast to other regions in the skeleton, labeled leukocyte imaging is not useful for diagnosing spinal osteomyelitis. At the moment, gallium is the preferred radionuclide procedure for this condition and is a useful adjunct to magnetic resonance imaging. FDG-PET likely will play an important role in the evaluation of musculoskeletal infection, especially spinal osteomyelitis, and may replace gallium imaging for this purpose. (author)

  6. Terrestrial pathways of radionuclide particulates

    International Nuclear Information System (INIS)

    Boone, F.W.; Ng, Y.C.

    1981-01-01

    Formulations are developed for computing potential human intake of 13 radionuclides via the terrestrial food chains. The formulations are an extension of the NRC methodology. Specific regional crop and livestock transfer and fractional distribution data from the southern part of the U.S.A. are provided and used in the computation of comparative values with those computed by means of USNRC Regulatory Guide 1.109 formulations. In the development of the model, emphasis was also placed on identifying the various time-delay compartments of the food chains and accounting for all of the activity initially deposited. For all radionuclides considered, except 137 Cs, the new formulations predict lower potential intakes from the total of all food chains combined than do the comparable Regulatory Guide formulations by as much as a factor of 40. For 137 Cs the new formulations predict 10% higher potential intakes. (author)

  7. Radionuclide cinematography of the heart

    International Nuclear Information System (INIS)

    Adam, W.E.; Sigel, H.; Geffers, H.; Bitter, F.; Meyer, G.; Kampmann, H.; Stauch, M.

    1976-01-01

    Radionuclide cinematography is described as a procedure making use of radiation-level variations above the heart after equipartitioning of sup(99m)Tc-labelled human serum albumin in the blood pool. Regional ventricular and vestibular variations are phase-shifted. This procedure permits delineation of aneurysmas with interphasic course, cicatrization of the cardiac wall not producing any cyclical variation. The study included normal subjects and 16 patients with full course infarction. Characteristic disturbances of motility distribution were found in all cases of scarred or aneurysmic alterations in the frontal and side walls of the left ventricle. The procedure was unable to detect two small infarction scars on the rear wall. The possibility of using radionuclide cinematography to prove coronary insufficiency as well as a comparison with other methods are discussed

  8. Radionuclide 252Cf neutron source

    International Nuclear Information System (INIS)

    Kolevatov, Yu.I.; Trykov, L.A.

    1979-01-01

    Characteristics of radionuclide neutron sourses of 252 Cf base with the activity from 10 6 to 10 9 n/s have been investigated. Energetic distributions of neutrons and gamma-radiation have been presented. The results obtained have been compared with other data available. The hardness parameter of the neutron spectrum for the energy range from 3 to 15 MeV is 1.4 +- 0.02 MeV

  9. Radionuclide diagnosis of Meckel's diverticulum

    International Nuclear Information System (INIS)

    Conway, J.J.; Northwestern Univ., Chicago, IL

    1980-01-01

    Meckel's diverticulum can be detected with a high degree of accuracy by radionuclide scintigraphy using technetium-99m pertechnetate. The technique is without risk and should precede roentgenographic studies when the diagnosis is suspected. The method is described and the causes for false positive and false negative examinations are discussed. False negatives are rare and false positives are usually secondary to other surgical entities. Overall accuracy is 85 to 90%. (orig.) [de

  10. Radionuclides for therapy: a review

    International Nuclear Information System (INIS)

    Roesler, H.; Noelpp, U.; Triller, K.J.; Steffen, R.

    1986-01-01

    Progress in angiographic techniques has been a gradual evolutionary development which now permits the selective and superselective access to a tumor's vascular bed. A diagnostic angiographic procedure can be supplemented by a one-step, quick application of embolizing radioactive material. This endoarterial radionuclide embolizing tumor therapy has the maximum selectivity among radiotherapeutic methods, with the highest radiation doses to the tumor and neglectible exposure of normal tissue. Spread of radioactivity by diffusion or leaching can be prevented

  11. Radionuclide dispersion in the atmosphere

    International Nuclear Information System (INIS)

    Moura Neto, C. de; Amorim, E.S. do; Panetta, J.

    1979-05-01

    The instantaneous liberation of radionuclides in the atmosphere is studied in three dimensions, according to the formalism of the diffusion theory. The analytical solution, expose to gravitational and an atmospherical effects, is combined with the discretization of space and time in the calculation of levels of exposure. A typical inventory (for a PWR) was considered in the calculation of immersion doses, and the results permitted a comparative analysis among the different existing models. (Author) [pt

  12. Radiation protection in radionuclide investigations

    International Nuclear Information System (INIS)

    Taylor, D.M.

    1985-01-01

    The subject is covered in sections: introduction; radiation and radioactivity; alpha particles; beta particles; neutrons; electromagnetic radiation; units of radioactivity and radiation; biological effects of radiation; the philosophy of radiation protection (ALARA principle); practical aspects of radiation protection; work with unsealed radiation sources; radionuclide studies in experimental animals; radiation safety during clinical investigations; legislative control of radiation work; radioactive waste disposal; emergency procedures; conclusion. (U.K.)

  13. Radionuclide evaluation of renal transplants

    International Nuclear Information System (INIS)

    Yang Hong; Zhao Deshan

    2000-01-01

    Radionuclide renal imaging and plasma clearance methods can quickly quantitate renal blood flow and function in renal transplants. They can diagnose acute tubular necrosis and rejection, renal scar, surgical complications such as urine leaks, obstruction and renal artery stenosis after renal transplants. At the same time they can assess the therapy effect of renal transplant complications and can also predict renal transplant survival from early post-operative function studies

  14. Chief, Structural Biophysics Laboratory | Center for Cancer Research

    Science.gov (United States)

    The SBL Chief is expected to establish a strong research program in structural biology/biophysics in addition to providing leadership of the SBL and the structural biology community in the NCI Intramural Program.  Applicants should hold a Ph.D., M.D./Ph.D., or equivalent doctoral degree in a relevant discipline, and should possess outstanding communication skills and documented leadership experience.  Tenured faculty or industrial scientists of equivalent rank with a demonstrated commitment to structural biophysics should apply.  Salary will be commensurate with experience and accomplishments.  This position is not restricted to U.S. citizens. A full civil service package of benefits (including health insurance, life insurance, and retirement) is available. This position is subject to a background investigation.  The NIH is dedicated to building a diverse community in its training and employment programs.

  15. Synthetic Biology: Engineering Living Systems from Biophysical Principles.

    Science.gov (United States)

    Bartley, Bryan A; Kim, Kyung; Medley, J Kyle; Sauro, Herbert M

    2017-03-28

    Synthetic biology was founded as a biophysical discipline that sought explanations for the origins of life from chemical and physical first principles. Modern synthetic biology has been reinvented as an engineering discipline to design new organisms as well as to better understand fundamental biological mechanisms. However, success is still largely limited to the laboratory and transformative applications of synthetic biology are still in their infancy. Here, we review six principles of living systems and how they compare and contrast with engineered systems. We cite specific examples from the synthetic biology literature that illustrate these principles and speculate on their implications for further study. To fully realize the promise of synthetic biology, we must be aware of life's unique properties. Copyright © 2017 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  16. From hadron therapy to cosmic rays: a life in biophysics

    CERN Multimedia

    Christine Sutton

    2014-01-01

    In 1954 – the year CERN was founded – another scientific journey began at what is now the Lawrence Berkeley National Laboratory. Beams of protons from a particle accelerator were used for the first time by John Lawrence – a doctor and the brother of Ernest Lawrence, the physicist after whom the Berkeley lab is named – to treat patients with cancer. For many years, Eleanor Blakely has been one of the leaders of that journey. She visited CERN last week and spoke with the Bulletin about her life in biophysics.   Use of the cylcotron beam to mimic "shooting stars" seen by astronauts. Black hood on subject Cornelius Tobias keeps out light during neutron irradiation experiment at the 184-inch accelerator. Helping to position Tobias in the beam line are (left to right) John Lyman of Biomedical Division, and Ralph Thomas of Health Physics. (Photo courtesy of Lawrence Berkeley National Laboratory.) Interested in biophysics, which was still a new...

  17. Achievements and challenges in structural bioinformatics and computational biophysics.

    Science.gov (United States)

    Samish, Ilan; Bourne, Philip E; Najmanovich, Rafael J

    2015-01-01

    The field of structural bioinformatics and computational biophysics has undergone a revolution in the last 10 years. Developments that are captured annually through the 3DSIG meeting, upon which this article reflects. An increase in the accessible data, computational resources and methodology has resulted in an increase in the size and resolution of studied systems and the complexity of the questions amenable to research. Concomitantly, the parameterization and efficiency of the methods have markedly improved along with their cross-validation with other computational and experimental results. The field exhibits an ever-increasing integration with biochemistry, biophysics and other disciplines. In this article, we discuss recent achievements along with current challenges within the field. © The Author 2014. Published by Oxford University Press.

  18. Evolution and Biophysics of the Escherichia coli lac Operon

    Science.gov (United States)

    Ray, J. Christian; Igoshin, Oleg; Quan, Selwyn; Monds, Russell; Cooper, Tim; Balázsi, Gábor

    2011-03-01

    To understand, predict, and control the evolution of living organisms, we consider biophysical effects and molecular network architectures. The lactose utilization system of E. coli is among the most well-studied molecular networks in biology, making it an ideal candidate for such studies. Simulations show how the genetic architecture of the wild-type operon attenuates large metabolic intermediate fluctuations that are predicted to occur in an equivalent system with the component genes on separate operons. Quantification of gene expression in the lac operon evolved in growth conditions containing constant lactose, alternating with glucose, or constant glucose, shows characteristic gene expression patterns depending on conditions. We are simulating these conditions to show context-dependent biophysical sources and costs of different lac operon architectures.

  19. Biophysical dosimetry using electron paramagnetic resonance in human tooth

    International Nuclear Information System (INIS)

    Khan, R.F.H.; Boreham, D.R.; Rink, W.J.

    2002-01-01

    Accidental dosimetry utilizing radiation induced paramagnetic species in biophysical tissues like teeth is a technique; that can measure the amount of radiation exposure to an individual. The major problem in implementing this technique at low doses is the presence of native organic signal, and various other artifacts produced as a result of sample processing. After a series of experimental trials, we developed an optimum set of rules, which uses high temperature ultrasonic treatment of enamel in KOH, multiple sample rotation during in-cavity measurement of natural and calibrated added irradiations, and dose construction using a backward extrapolation method. By using this we report the successful dose reconstruction in a few of our laboratory samples in 100 mGy range (76.29 ± 30.14) mGy with reasonably low uncertainty. Keywords: biophysical dosimetry, human tooth enamel, low dose measurements, accidental dosimetry (author)

  20. The biophysics of renal sympathetic denervation using radiofrequency energy.

    Science.gov (United States)

    Patel, Hitesh C; Dhillon, Paramdeep S; Mahfoud, Felix; Lindsay, Alistair C; Hayward, Carl; Ernst, Sabine; Lyon, Alexander R; Rosen, Stuart D; di Mario, Carlo

    2014-05-01

    Renal sympathetic denervation is currently performed in the treatment of resistant hypertension by interventionists who otherwise do not typically use radiofrequency (RF) energy ablation in their clinical practice. Adequate RF lesion formation is dependent upon good electrode-tissue contact, power delivery, electrode-tissue interface temperature, target-tissue impedance and the size of the catheter's active electrode. There is significant interplay between these variables and hence an appreciation of the biophysical determinants of RF lesion formation is required to provide effective and safe clinical care to our patients. In this review article, we summarize the biophysics of RF ablation and explain why and how complications of renal sympathetic denervation may occur and discuss methods to minimise them.

  1. Biophysical Evaluation of Food Decontamination Effects on Tissue and Bacteria

    DEFF Research Database (Denmark)

    Andersen, Ann Zahle; Duelund, Lars; Brewer, Jonathan

    2011-01-01

    Traditionally, the effects and efficiency of food surface decontamination processes, such as chlorine washing, radiation, or heating, have been evaluated by sensoric analysis and colony-forming unit (CFU) counts of surface swabs or carcass rinses. These methods suffice when determining probable...... consumer responses or meeting legislative contamination limits. However, in the often very costly, optimization process of a new method, more quantitative and unbiased results are invaluable. In this study, we employed a biophysical approach for the investigation of qualitative and quantitative changes...... that there are no contradictions between data obtained by either approach. However, the biophysical methods draw a much more nuanced picture of the effects and efficiency of the investigated decontamination method, revealing, e.g., an exponential dose/response relationship between SonoSteam® treatment time and changes in collagen...

  2. Radionuclide behavior in the environment

    International Nuclear Information System (INIS)

    Tveten, U.

    1991-09-01

    The purpose of this report is to document the results of the following task: Review for quality and consistency the available data on measurements of initial ground contamination of Chernobyl radionuclides in various parts of Norway and subsequent concentrations of these radionuclides in various environmental media as functions of time. Utilize the data obtained to verify the existing models, or to improve them, for describing radionuclide behavior in the environment. Some of the processes standard were: migration into soil; weathering; resuspension; food-chain contamination; and loss or reconcentration by run-off. The task performed within this contract has been to use post-Chernobyl data from Norway to verify or find areas for possible improvement in the chronic exposure pathway models utilized in MACCS. Work has consisted mainly of collecting and evaluating post-Chernobyl information from Norway or other countries when relevant; but has also included experimental work performed specifically for the current task. In most connections the data available show the models and data in MACCS to be appropriate. A few areas where the data indicate that the MACCS approach is faulty or inadequate are, however, pointed out in the report. These should be examined carefully, and appropriate modifications should eventually be made. 14 refs., 12 figs., 22 tabs

  3. Biophysical and electrochemical studies of protein-nucleic acid interactions

    Czech Academy of Sciences Publication Activity Database

    Bowater, R. P.; Cobb, A:M.; Pivoňková, Hana; Havran, Luděk; Fojta, Miroslav

    2015-01-01

    Roč. 146, č. 5 (2015), s. 723-739 ISSN 0026-9247 R&D Projects: GA ČR(CZ) GBP206/12/G151; GA ČR(CZ) GAP301/11/2076 Institutional support: RVO:68081707 Keywords : ISOTHERMAL TITRATION CALORIMETRY * OSMIUM-TETROXIDE COMPLEXES * SURFACE-PLASMON RESONANCE Subject RIV: BO - Biophysics Impact factor: 1.131, year: 2015

  4. Raman spectroscopy reveals biophysical markers in skin cancer surgical margins

    Science.gov (United States)

    Feng, Xu; Moy, Austin J.; Nguyen, Hieu T. M.; Zhang, Yao; Fox, Matthew C.; Sebastian, Katherine R.; Reichenberg, Jason S.; Markey, Mia K.; Tunnell, James W.

    2018-02-01

    The recurrence rate of nonmelanoma skin cancer is highly related to the residual tumor after surgery. Although tissueconserving surgery, such as Mohs surgery, is a standard method for the treatment of nonmelanoma skin cancer, they are limited by lengthy and costly frozen-section histopathology. Raman spectroscopy (RS) is proving to be an objective, sensitive, and non-destructive tool for detecting skin cancer. Previous studies demonstrated the high sensitivity of RS in detecting tumor margins of basal cell carcinoma (BCC). However, those studies rely on statistical classification models and do not elucidate the skin biophysical composition. As a result, we aim to discover the biophysical differences between BCC and primary normal skin structures (including epidermis, dermis, hair follicle, sebaceous gland and fat). We obtained freshly resected ex vivo skin samples from fresh resection specimens from 14 patients undergoing Mohs surgery. Raman images were acquired from regions containing one or more structures using a custom built 830nm confocal Raman microscope. The spectra were grouped using K-means clustering analysis and annotated as either BCC or each of the five normal structures by comparing with the histopathology image of the serial section. The spectral data were then fit by a previously established biophysical model with eight primary skin constituents. Our results show that BCC has significant differences in the fit coefficients of nucleus, collagen, triolein, keratin and elastin compared with normal structures. Our study reveals RS has the potential to detect biophysical changes in resection margins, and supports the development of diagnostic algorithms for future intraoperative implementation of RS during Mohs surgery.

  5. TH-AB-206-01: Advances in Radionuclide Therapy - From Radioiodine to Nanoparticles

    International Nuclear Information System (INIS)

    Humm, J.

    2016-01-01

    In the past few decades, the field of nuclear medicine has made long strides with the continued advancement of related sciences and engineering and the availability of diagnostic and therapeutic radionuclides. Leveraging these advancements while combining the advantages of therapeutic and diagnostic radionuclides into one radiopharmaceutical has also created a new subfield “theranostics” in nuclear medicine that has the potential to further propel the field into the future. This session is composed of two talks; one focused on the physics principles of theranostics from properties of beta and alpha emitting radionuclides to dosimetric models and quantification; while the second describes preclinical and clinical applications of theranostics and discusses the challenges and opportunities of bringing them to the clinic. At the end of the session the listener should be able to identify: The different properties of beta and alpha emitting radionuclides Which radionuclides are selected for which nuclear medicine therapies and why How PET can be used to accurately quantify the uptake of tumor targeting molecules How individualized dosimetry can be performed from the management of thyroid cancer to novel radiolabeled antibody therapies Promising pre-clinical radiopharmaceutical pairs in prostate cancer and melanoma. Promising clinical Theranostics in neuroendocrine cancers. Challenges of bringing Theranostics to the clinic. E. Delpassand, RITA Foundation -Houston; SBIR Grant; CEO and share holder of RadioMedix.

  6. TH-AB-206-01: Advances in Radionuclide Therapy - From Radioiodine to Nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Humm, J. [Memorial Sloan-Kettering Cancer Center (United States)

    2016-06-15

    In the past few decades, the field of nuclear medicine has made long strides with the continued advancement of related sciences and engineering and the availability of diagnostic and therapeutic radionuclides. Leveraging these advancements while combining the advantages of therapeutic and diagnostic radionuclides into one radiopharmaceutical has also created a new subfield “theranostics” in nuclear medicine that has the potential to further propel the field into the future. This session is composed of two talks; one focused on the physics principles of theranostics from properties of beta and alpha emitting radionuclides to dosimetric models and quantification; while the second describes preclinical and clinical applications of theranostics and discusses the challenges and opportunities of bringing them to the clinic. At the end of the session the listener should be able to identify: The different properties of beta and alpha emitting radionuclides Which radionuclides are selected for which nuclear medicine therapies and why How PET can be used to accurately quantify the uptake of tumor targeting molecules How individualized dosimetry can be performed from the management of thyroid cancer to novel radiolabeled antibody therapies Promising pre-clinical radiopharmaceutical pairs in prostate cancer and melanoma. Promising clinical Theranostics in neuroendocrine cancers. Challenges of bringing Theranostics to the clinic. E. Delpassand, RITA Foundation -Houston; SBIR Grant; CEO and share holder of RadioMedix.

  7. Radionuclide daughter inventory generator code: DIG

    International Nuclear Information System (INIS)

    Fields, D.E.; Sharp, R.D.

    1985-09-01

    The Daughter Inventory Generator (DIG) code accepts a tabulation of radionuclide initially present in a waste stream, specified as amounts present either by mass or by activity, and produces a tabulation of radionuclides present after a user-specified elapsed time. This resultant radionuclide inventory characterizes wastes that have undergone daughter ingrowth during subsequent processes, such as leaching and transport, and includes daughter radionuclides that should be considered in these subsequent processes or for inclusion in a pollutant source term. Output of the DIG code also summarizes radionuclide decay constants. The DIG code was developed specifically to assist the user of the PRESTO-II methodology and code in preparing data sets and accounting for possible daughter ingrowth in wastes buried in shallow-land disposal areas. The DIG code is also useful in preparing data sets for the PRESTO-EPA code. Daughter ingrowth in buried radionuclides and in radionuclides that have been leached from the wastes and are undergoing hydrologic transport are considered, and the quantities of daughter radionuclide are calculated. Radionuclide decay constants generated by DIG and included in the DIG output are required in the PRESTO-II code input data set. The DIG accesses some subroutines written for use with the CRRIS system and accesses files containing radionuclide data compiled by D.C. Kocher. 11 refs

  8. Radionuclide migration test using undisturbed aerated soil

    International Nuclear Information System (INIS)

    Yamamoto, Tadatoshi; Ohtsuka, Yoshiro; Ogawa, Hiromichi; Wadachi, Yoshiki

    1988-01-01

    As one of the most important part of safety assessment on the shallow land disposal of lowlevel radioactive waste, the radionuclide migration was studied using undisturbed soil samples, in order to evaluate an exact radionuclide migration in an aerated soil layer. Soil samples used in the migration test were coastal sand and loamy soil which form typical surface soil layers in Japan. The aqueous solution containing 60 CoCl 2 , 85 SrCl 2 and 137 CsCl was fed into the soil column and concentration of each radionuclide both in effluent and in soil was measured. Large amount of radionuclides was adsorbed on the surface of soil column and small amount of radionuclides moved deep into the soil column. Difference in the radionuclide profile was observed in the low concentration portion particularly. It is that some fractions of 60 Co and 137 Cs are stable in non-ionic form and move downward through the soil column together with water. The radionuclide distribution in the surface of soil column can be fairly predicted with a conventional migration equation for ionic radionuclides. As a result of radionuclide adsorption, both aerated soil layers of coastal sand and loamy soil have large barrier ability on the radionuclide migration through the ground. (author)

  9. Metabolism of radionuclides in domestic animals

    International Nuclear Information System (INIS)

    Wirth, E.; Leising, C.

    1986-01-01

    The reactor accident at Chernobyl has shown that shortly after the contamination of the environment radionuclides can be found in animal products. The main contamination pathways of domestic animas are: uptake of radionuclides by foodstuffs; uptake of radionuclides by contaminated drinking water; uptake of radionuclides by inhalation; uptake of radionuclides through skin; uptake of radionuclides by ingestion of soil particles. Generally the uptake of radionuclides by food is the dominant exposure pathway. In rare cases the inhalation of radionuclides or the uptake by drinking water may be of importance. The metabolism of incorporated radionuclides is comparable to the respective metabolism of essential mass or trace elements or heavy metals. Radioisotopes of essential elements are for instance iron 55, manganese 54, cobalt 58 and cobalt 60. Other elements are typical antagonists to essential elements, e.g. strontium 90 is an antagonist to calcium or cesium 137 to potassium. Lead 210 and plutonium 239 behave similarly as heavy metals. Generally the knowledge of the metabolism of trace and mass elements, of antagonistic and synergistic elements and heavy metals can be applied to these radionuclides

  10. A quantitative overview of biophysical forces impinging on neural function

    International Nuclear Information System (INIS)

    Mueller, Jerel K; Tyler, William J

    2014-01-01

    The fundamentals of neuronal membrane excitability are globally described using the Hodgkin-Huxley (HH) model. The HH model, however, does not account for a number of biophysical phenomena associated with action potentials or propagating nerve impulses. Physical mechanisms underlying these processes, such as reversible heat transfer and axonal swelling, have been compartmentalized and separately investigated to reveal neuronal activity is not solely influenced by electrical or biochemical factors. Instead, mechanical forces and thermodynamics also govern neuronal excitability and signaling. To advance our understanding of neuronal function and dysfunction, compartmentalized analyses of electrical, chemical, and mechanical processes need to be revaluated and integrated into more comprehensive theories. The present perspective is intended to provide a broad overview of biophysical forces that can influence neural function, but which have been traditionally underappreciated in neuroscience. Further, several examples where mechanical forces have been shown to exert their actions on nervous system development, signaling, and plasticity are highlighted to underscore their importance in sculpting neural function. By considering the collective actions of biophysical forces influencing neuronal activity, our working models can be expanded and new paradigms can be applied to the investigation and characterization of brain function and dysfunction. (topical review)

  11. Modelling benthic biophysical drivers of ecosystem structure and biogeochemical response

    Science.gov (United States)

    Stephens, Nicholas; Bruggeman, Jorn; Lessin, Gennadi; Allen, Icarus

    2016-04-01

    The fate of carbon deposited at the sea floor is ultimately decided by biophysical drivers that control the efficiency of remineralisation and timescale of carbon burial in sediments. Specifically, these drivers include bioturbation through ingestion and movement, burrow-flushing and sediment reworking, which enhance vertical particulate transport and solute diffusion. Unfortunately, these processes are rarely satisfactorily resolved in models. To address this, a benthic model that explicitly describes the vertical position of biology (e.g., habitats) and biogeochemical processes is presented that includes biological functionality and biogeochemical response capturing changes in ecosystem structure, benthic-pelagic fluxes and biodiversity on inter-annual timescales. This is demonstrated by the model's ability to reproduce temporal variability in benthic infauna, vertical pore water nutrients and pelagic-benthic solute fluxes compared to in-situ data. A key advance is the replacement of bulk parameterisation of bioturbation by explicit description of the bio-physical processes responsible. This permits direct comparison with observations and determination of key parameters in experiments. Crucially, the model resolves the two-way interaction between sediment biogeochemistry and ecology, allowing exploration of the benthic response to changing environmental conditions, the importance of infaunal functional traits in shaping benthic ecological structure and the feedback the resulting bio-physical processes exert on pore water nutrient profiles. The model is actively being used to understand shelf sea carbon cycling, the response of the benthos to climatic change, food provision and other societal benefits.

  12. Antimicrobial and biophysical properties of surfactant supplemented with an antimicrobial peptide for treatment of bacterial pneumonia.

    Science.gov (United States)

    Banaschewski, Brandon J H; Veldhuizen, Edwin J A; Keating, Eleonora; Haagsman, Henk P; Zuo, Yi Y; Yamashita, Cory M; Veldhuizen, Ruud A W

    2015-01-01

    Antibiotic-resistant bacterial infections represent an emerging health concern in clinical settings, and a lack of novel developments in the pharmaceutical pipeline is creating a "perfect storm" for multidrug-resistant bacterial infections. Antimicrobial peptides (AMPs) have been suggested as future therapeutics for these drug-resistant bacteria, since they have potent broad-spectrum activity, with little development of resistance. Due to the unique structure of the lung, bacterial pneumonia has the additional problem of delivering antimicrobials to the site of infection. One potential solution is coadministration of AMPs with exogenous surfactant, allowing for distribution of the peptides to distal airways and opening of collapsed lung regions. The objective of this study was to test various surfactant-AMP mixtures with regard to maintaining pulmonary surfactant biophysical properties and bactericidal functions. We compared the properties of four AMPs (CATH-1, CATH-2, CRAMP, and LL-37) suspended in bovine lipid-extract surfactant (BLES) by assessing surfactant-AMP mixture biophysical and antimicrobial functions. Antimicrobial activity was tested against methillicin-resistant Staphylococcus aureus and Pseudomonas aeruginosa. All AMP/surfactant mixtures exhibited an increase of spreading compared to a BLES control. BLES+CATH-2 mixtures had no significantly different minimum surface tension versus the BLES control. Compared to the other cathelicidins, CATH-2 retained the most bactericidal activity in the presence of BLES. The BLES+CATH-2 mixture appears to be an optimal surfactant-AMP mixture based on in vitro assays. Future directions involve investigating the potential of this mixture in animal models of bacterial pneumonia. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  13. Methods of separating short half-life radionuclides from a mixture of radionuclides

    Science.gov (United States)

    Bray, Lane A.; Ryan, Jack L.

    1998-01-01

    The present invention is a method of obtaining a radionuclide product selected from the group consisting of .sup.223 Ra and .sup.225 Ac, from a radionuclide "cow" of .sup.227 Ac or .sup.229 Th respectively. The method comprises the steps of a) permitting ingrowth of at least one radionuclide daughter from said radionuclide "cow" forming an ingrown mixture; b) insuring that the ingrown mixture is a nitric acid ingrown mixture; c) passing the nitric acid ingrown mixture through a first nitrate form ion exchange column which permits separating the "cow" from at least one radionuclide daughter; d) insuring that the at least one radionuclide daughter contains the radionuclide product; e) passing the at least one radionuclide daughter through a second ion exchange column and separating the at least one radionuclide daughter from the radionuclide product and f) recycling the at least one radionuclide daughter by adding it to the "cow". In one embodiment the radionuclide "cow" is the .sup.227 Ac, the at least one daughter radionuclide is a .sup.227 Th and the product radionuclide is the .sup.223 Ra and the first nitrate form ion exchange column passes the .sup.227 Ac and retains the .sup.227 Th. In another embodiment the radionuclide "cow"is the .sup.229 Th, the at least one daughter radionuclide is a .sup.225 Ra and said product radionuclide is the .sup.225 Ac and the .sup.225 Ac and nitrate form ion exchange column retains the .sup.229 Th and passes the .sup.225 Ra/Ac.

  14. The potential of 211Astatine for NIS-mediated radionuclide therapy in prostate cancer

    International Nuclear Information System (INIS)

    Willhauck, Michael J.; Sharif Samani, Bibi-Rana; Goeke, Burkhard; Wolf, Ingo; Senekowitsch-Schmidtke, Reingard; Stark, Hans-Juergen; Meyer, Geerd J.; Knapp, Wolfram H.; Morris, John C.; Spitzweg, Christine

    2008-01-01

    We reported recently the induction of selective iodide uptake in prostate cancer cells (LNCaP) by prostate-specific antigen (PSA) promoter-directed sodium iodide symporter (NIS) expression that allowed a significant therapeutic effect of 131 I. In the current study, we studied the potential of the high-energy alpha-emitter 211 At, also transported by NIS, as an alternative radionuclide after NIS gene transfer in tumors with limited therapeutic efficacy of 131 I due to rapid iodide efflux. We investigated uptake and therapeutic efficacy of 211 At in LNCaP cells stably expressing NIS under the control of the PSA promoter (NP-1) in vitro and in vivo. NP-1 cells concentrated 211 At in a perchlorate-sensitive manner, which allowed a dramatic therapeutic effect in vitro. After intrapertoneal injection of 211 At (1 MBq), NP-1 tumors accumulated approximately 16% ID/g 211 At (effective half-life 4.6 h), which resulted in a tumor-absorbed dose of 1,580 ± 345 mGy/MBq and a significant tumor volume reduction of up to 82 ± 19%, while control tumors continued their growth exponentially. A significant therapeutic effect of 211 At has been demonstrated in prostate cancer after PSA promoter-directed NIS gene transfer in vitro and in vivo suggesting a potential role for 211 At as an attractive alternative radioisotope for NIS-targeted radionuclide therapy, in particular in smaller tumors with limited radionuclide retention time. (orig.)

  15. The dynamics of immunologic reactions in rats affected by repeated external γ-irradiation and internal irradiation with radionuclides

    International Nuclear Information System (INIS)

    Shubik, V.M.; Livshits, R.E.

    1975-01-01

    Nonspecific factors of immunity and formation of autoantibodies in rats exposed to comparable doses of repeated external γ-irradiation and of internal irradiation with Cs 137 , Sr 90 and I 131 chronically administered to animals have been studied comparatively. No essential variations have been found in changes induced in the immunologic reactions by chronic external and even internal γ-irradiation. Certain peculiarities have been revealed in the character of changes in the immunologic reactions depending on biophysical properties of the radionuclides used in the experiments

  16. 188Re(V) Nitrido Radiopharmaceuticals for Radionuclide Therapy.

    Science.gov (United States)

    Boschi, Alessandra; Martini, Petra; Uccelli, Licia

    2017-01-19

    The favorable nuclear properties of rhenium-188 for therapeutic application are described, together with new methods for the preparation of high yield and stable 188 Re radiopharmaceuticals characterized by the presence of the nitride rhenium core in their final chemical structure. 188 Re is readily available from an 188 W/ 188 Re generator system and a parallelism between the general synthetic procedures applied for the preparation of nitride technetium-99m and rhenium-188 theranostics radiopharmaceuticals is reported. Although some differences between the chemical characteristics of the two metallic nitrido fragments are highlighted, it is apparent that the same general procedures developed for the labelling of biologically active molecules with technetium-99m can be applied to rhenium-188 with minor modification. The availability of these chemical strategies, that allow the obtainment, in very high yield and in physiological condition, of 188 Re radiopharmaceuticals, gives a new attractive prospective to employ this radionuclide for therapeutic applications.

  17. 188Re(V) Nitrido Radiopharmaceuticals for Radionuclide Therapy

    Science.gov (United States)

    Boschi, Alessandra; Martini, Petra; Uccelli, Licia

    2017-01-01

    The favorable nuclear properties of rhenium-188 for therapeutic application are described, together with new methods for the preparation of high yield and stable 188Re radiopharmaceuticals characterized by the presence of the nitride rhenium core in their final chemical structure. 188Re is readily available from an 188W/188Re generator system and a parallelism between the general synthetic procedures applied for the preparation of nitride technetium-99m and rhenium-188 theranostics radiopharmaceuticals is reported. Although some differences between the chemical characteristics of the two metallic nitrido fragments are highlighted, it is apparent that the same general procedures developed for the labelling of biologically active molecules with technetium-99m can be applied to rhenium-188 with minor modification. The availability of these chemical strategies, that allow the obtainment, in very high yield and in physiological condition, of 188Re radiopharmaceuticals, gives a new attractive prospective to employ this radionuclide for therapeutic applications. PMID:28106830

  18. Phytoremediation of radionuclides: an emerging alternative

    International Nuclear Information System (INIS)

    Singh, Shraddha

    2013-01-01

    Proliferation of nuclear power industry, nuclear weapon testing, dismantling of existing nuclear weapons and occasional accidents have contributed to an enhancement in the level of radionuclides in the environment. The radionuclides due to their long half life and transfer through the food chain effect adversely to normal biological systems. Hence, it is essential to effectively remove the radionuclides from contaminated soils and solutions. Phytoremediation - the use of plants for remediation of toxic metals and radionuclides has been recognized as an aesthetically pleasing, low cost and environment friendly in situ method. Phytoremediation is an umbrella term which covers several plant based approaches. Plants have shown the potential of remediation of these radionuclides from spiked solutions, low level nuclear waste and soil. Various aspects of phytoremediation as well as potential of various plants for remediation of radionuclides will be discussed here. (author)

  19. Radionuclide transport processes in terrestrial ecosystems

    International Nuclear Information System (INIS)

    Whicker, F.W.

    1983-01-01

    Some major principles and the status of knowledge concerning the transport of radionuclides through terrestrial ecosystems are reviewed. Fundamental processes which control the flow of radionuclides between ecosystem components such as air, soil, plants, and animals are described, with emphasis on deposition, resuspension, plant uptake, ingestion, and assimilation. Properties of radionuclides, organisms, and ecosystems are examined in relation to their influence on the accumulation of radioactive materials by plants and animals. The effects of the physicochemical nature of the radionuclide; morphology, physiology, and behavior of the organism; and soil, nutrient, and trophic characteristics of the ecosystem are highlighted. Observations in natural ecosystems on radionuclides such as 137 Cs, 90 Sr, 131 I, 3 H, and 239 Pu are used to illustrate current concepts. An assessment of the degree to which the processes controlling radionuclide behavior are understood and of our ability to simulate and predict such behavior with computerized models is offered. Finally, brief comments are made on research needs

  20. Radionuclides in the study of marine processes

    International Nuclear Information System (INIS)

    Kershaw, P.J.; Woodhead, D.S.

    1991-01-01

    For many years, the radioactive properties of the naturally occurring radionuclides have been used to determine their distributions in the marine environment and, more generally, to gain an understanding of the dynamic processes which control their behaviour in attaining these distributions. More recently the inputs from human activities of both natural and artificial (i.e. man-made) radionuclides have provided additional opportunities for the study of marine processes on local, regional and global scales. The primary objective of the symposium is to provide a forum for an open discussion of the insights concerning processes in the marine environment which can be gained from studies of radionuclide behaviour. Papers have been grouped within the following principal themes; the uses of radionuclides as tracers of water transport; scavenging and particulate transport processes in the oceans as deduced from radionuclide behaviour; processes in the seabed and radionuclides in biological systems. (Author)

  1. Chemical speciation of radionuclides migrating in groundwaters

    International Nuclear Information System (INIS)

    Robertson, D.; Schilk, A.; Abel, K.; Lepel, E.; Thomas, C.; Pratt, S.; Cooper, E.; Hartwig, P.; Killey, R.

    1994-04-01

    In order to more accurately predict the rates and mechanisms of radionuclide migration from low-level waste disposal facilities via groundwater transport, ongoing studies are being conducted at field sites at Chalk River Laboratories to identify and characterize the chemical speciation of mobile, long-lived radionuclides migrating in groundwaters. Large-volume water sampling techniques are being utilized to separate and concentrate radionuclides into particular, cationic, anionic, and nonionic chemical forms. Most radionuclides are migrating as soluble, anionic species that appear to be predominantly organoradionuclide complexes. Laboratory studies utilizing anion exchange chromatography have separated several anionically complexed radionuclides, e.g., 60 Co and 106 Ru, into a number of specific compounds or groups of compounds. Further identification of the anionic organoradionuclide complexes is planned utilizing high resolution mass spectrometry. Large-volume ultra-filtration experiments are characterizing the particulate forms of radionuclides being transported in these groundwaters

  2. Production of radionuclides with generators

    International Nuclear Information System (INIS)

    Khujaev, S.; Egamediev, S.Kh.

    2004-01-01

    Full text: The radionuclide generator provides a convenient means for researchers and clinicians to obtain a source of radionuclides without dependence on nuclear facilities (nuclear reactor or cyclotron). It should be noted that radionuclide generator technique yields products of very high purity and it offers moreover the only possible way of obtaining very short-lived radionuclides for practical applications. Therefore at present radionuclide generators have found important uses in nuclear medicine. This talk reviews the development of preparation methods for radionuclide generators of current interest: 99 Mo- 99m Tc, 188 W- 188 Re and 68 Ge- 68 Ga. 99 Mo- 99m Tc generator. 99m Tc is presently the most widely used radionuclide in diagnostic nuclear medicine. The reason for such a preeminent position of 99m Tc in clinical uses is its extremely favorable nuclear properties with γ-energy of 140 keV and short half-life of 6 hours. Chromatographic generator of 99 Mo- 99m Tc based on aluminium oxide using as eluent of isotonic saline solution, containing nitrate-ions has been produced in INP AS RU. However, the main disadvantage of this generator is that the eluent-saline solution contains some amount of nitrate-ions. Nitrate-ions added to maximize and stabilize 99m Tc yields would interfere with the chemical reactions which involve Sn(II) reduction of the pertechnetate ion and which are used subsequently in the preparation of radiopharmaceuticals. Therefore we proposed the new method for preliminary treatment of aluminium oxide by the external gamma (Co-60) irradiation. It is found that the aluminium oxide has got electron-acceptor properties after gamma-irradiation. Adsorption of 99 Mo radionuclide as isopolymolybdate on gamma-irradiated aluminium oxide is very high and molybdenum is firmly retained. Adsorption capacity of gamma-irradiated aluminium oxide at pH 2-4 is 60-80 mg Mo per gram of Al 2 O 3 . The yields of 99m Tc from experimental generators remained high

  3. DKPRO: A radionuclide decay and reprocessing code

    International Nuclear Information System (INIS)

    Wootan, D.; Schmittroth, F.A.

    1997-01-01

    The DKPRO code solves the general problem of modeling complex nuclear wastes streams using ORIGEN2 radionuclide production files. There is a continuing need for estimates of Hanford radionuclides. Physical measurements are one basis; calculational estimates, the approach represented here, are another. Given a known nuclear fuel history, it is relatively straightforward to calculate radionuclide inventories with codes such as the widely-used Oak Ridge National Laboratory code ORIGEN2

  4. Radionuclide usage survey 1979-80

    International Nuclear Information System (INIS)

    Woods, M.J.

    1980-08-01

    Details of a survey by the Life Sciences Working Group of the International Committee for Radionuclide Metrology (ICRM) on radionuclide usage by medical physicists in 11 countries are presented. The results indicate that the radionuclide which will be of most significance in the future will be F-18, Fe-52, Ga-67, Ga-68, Kr-81m, Tc-99m, In-111, I-123, Xe-127 and Tl-201, (U.K.)

  5. Preparation of porous materials for radionuclides capture

    International Nuclear Information System (INIS)

    Bajzikova, Anna; Smrcek, Stanislav; Kozempel, Jan; Vlk, Martin; Barta, Jan

    2015-01-01

    Porous materials showing promise for radionuclide capture from water at contaminated sites were prepared. Nanoporous materials (size of pores 1-100 nm) and some polymers are well suited to this purpose owing their affinity for selected radionuclides. Nanoporous metal oxides and silica gel with styrene-divinylbenzene-TODGA-modified surface were prepared, characterized and tested for radionuclide ( 227 Ac, 227 Th, 223 Ra) capture efficiency. (orig.)

  6. Report on the Technical Meeting on Therapeutic Radiopharmaceuticals

    International Nuclear Information System (INIS)

    2009-01-01

    The purpose of the TM was to provide an experts' platform to facilitate exploring the current status and future directions on therapeutic radiopharmaceuticals. The invited talks and presentations in the TM were in the following topics: - Radionuclide Production; - Production and availability of alpha emitters and their radiopharmaceuticals; - Therapeutic radiopharmaceutical chemistry; - Targets and biological evaluation; - Medical physics and dosimetry; - Clinical applications including radioimmunotherapy and clinical needs; - Peptide receptor mediated therapy Panel discussions: - Radionuclide therapy using alpha emitters; - Regulatory challenges with therapeutic radiopharmaceuticals; - International activities in radionuclide therapy. he technical meeting generated a large interest among scientists and physicians working in the field of targeted therapy using radiopharmaceuticals. Participants from both developed and developing MS reported on recent developments on the research work and clinical studies going on in the field and provided their views on the future developments in this field. The unexpected high number of participants and the high number of presentations with exceptional quality underlines the great interest of scientists and professionals in therapeutic applications using radiolabelled drugs / biomolecules. The intensive discussions including panels specified the challenges in the future on developing novel agents and to finally use them for the benefit of patients. The IAEA can play as vital role in streamlining developments and to provide tools to overcome scientific, professional and regulatory challenges in the field of therapeutic radiopharmaceuticals

  7. Report on the Technical Meeting on Therapeutic Radiopharmaceuticals

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    The purpose of the TM was to provide an experts' platform to facilitate exploring the current status and future directions on therapeutic radiopharmaceuticals. The invited talks and presentations in the TM were in the following topics: - Radionuclide Production; - Production and availability of alpha emitters and their radiopharmaceuticals; - Therapeutic radiopharmaceutical chemistry; - Targets and biological evaluation; - Medical physics and dosimetry; - Clinical applications including radioimmunotherapy and clinical needs; - Peptide receptor mediated therapy Panel discussions: - Radionuclide therapy using alpha emitters; - Regulatory challenges with therapeutic radiopharmaceuticals; - International activities in radionuclide therapy. he technical meeting generated a large interest among scientists and physicians working in the field of targeted therapy using radiopharmaceuticals. Participants from both developed and developing MS reported on recent developments on the research work and clinical studies going on in the field and provided their views on the future developments in this field. The unexpected high number of participants and the high number of presentations with exceptional quality underlines the great interest of scientists and professionals in therapeutic applications using radiolabelled drugs / biomolecules. The intensive discussions including panels specified the challenges in the future on developing novel agents and to finally use them for the benefit of patients. The IAEA can play as vital role in streamlining developments and to provide tools to overcome scientific, professional and regulatory challenges in the field of therapeutic radiopharmaceuticals

  8. Radionuclide reporter gene imaging for cardiac gene therapy

    International Nuclear Information System (INIS)

    Inubushi, Masayuki; Tamaki, Nagara

    2007-01-01

    In the field of cardiac gene therapy, angiogenic gene therapy has been most extensively investigated. The first clinical trial of cardiac angiogenic gene therapy was reported in 1998, and at the peak, more than 20 clinical trial protocols were under evaluation. However, most trials have ceased owing to the lack of decisive proof of therapeutic effects and the potential risks of viral vectors. In order to further advance cardiac angiogenic gene therapy, remaining open issues need to be resolved: there needs to be improvement of gene transfer methods, regulation of gene expression, development of much safer vectors and optimisation of therapeutic genes. For these purposes, imaging of gene expression in living organisms is of great importance. In radionuclide reporter gene imaging, ''reporter genes'' transferred into cell nuclei encode for a protein that retains a complementary ''reporter probe'' of a positron or single-photon emitter; thus expression of the reporter genes can be imaged with positron emission tomography or single-photon emission computed tomography. Accordingly, in the setting of gene therapy, the location, magnitude and duration of the therapeutic gene co-expression with the reporter genes can be monitored non-invasively. In the near future, gene therapy may evolve into combination therapy with stem/progenitor cell transplantation, so-called cell-based gene therapy or gene-modified cell therapy. Radionuclide reporter gene imaging is now expected to contribute in providing evidence on the usefulness of this novel therapeutic approach, as well as in investigating the molecular mechanisms underlying neovascularisation and safety issues relevant to further progress in conventional gene therapy. (orig.)

  9. Environmental behaviour of radionuclides and transfer to man

    International Nuclear Information System (INIS)

    Smith, H.

    1982-01-01

    The environmental behaviour of the radionuclides making the major contribution to man's irradiation through diet is described. The following stages are emphasized: transfer of radionuclides to plants; transfer of radionuclides to animals; metabolism of inhaled or ingested radionuclides in animals providing food for man; transfer of radionuclides through the aquatic environment; application of food chain models. (43 references)

  10. Radionuclide accumulation peculiarities demonstrated by vegetable varieties

    International Nuclear Information System (INIS)

    Kruk, A.V.; Goncharenko, G.G.; Kilchevsky, A.V.

    2004-01-01

    This study focused on ecological and genetic aspects of radionuclide accumulation demonstrated by a number of vegetable varieties. The researches resulted in determining the cabbage varieties which were characterised by the minimal level of radionuclide accumulation. It was shown that the above varieties manifested the relation between radionuclide accumulation and morphobiological characteristics such as vegetation period duration and yield criteria. The study specified the genotypes with high ecological stability as regards to radionuclide accumulation: 'Beloruskaya 85' cabbage and 'Dokhodny' tomato showed the best response to Cs 137, while 'Beloruskaya 85', 'Rusinovka', 'Amager 611' cabbage varieties and 'Sprint' tomato showed the minimal level of Sr 90 accumulation. (authors)

  11. Therapy for incorporated radionuclides: scope and need

    International Nuclear Information System (INIS)

    Smith, V.H.

    1981-03-01

    In the United States the recent termination of funding for research on therapy for incorporated radionuclides has virtually halted progress on improved or new agents and procedures for removing radioactivity from the body. Research was eliminated, but is still needed on new removal agents, improved delivery system, in vitro test systems, and the toxicology of treatments. For many radionuclides, no adequate therapy exists. The relationship between radionuclide removal and reduction in cancer risk is still unanswered. Without proper research support, needed improvements in the treatment for incorporated radionuclides in the US are uncertain

  12. Targeted radionuclide therapy for solid tumors: An overview

    International Nuclear Information System (INIS)

    De Nardo, Sally J.; De Nardo, Gerald L.

    2006-01-01

    Although radioimmunotherapy (RIT) has been effective in non-Hodgkin's lymphoma (NHL) as a single agent, solid tumors have shown less clinically significant therapeutic response to RIT alone. The clinical impact of RIT or other forms of targeted radionuclide therapy for solid tumors depends on the development of a high therapeutic index (TI) for the tumor vs. normal tissue effect, and the implementation of RIT as part of synergistic combined modality therapy (CMRIT). Preclinical and clinical studies have provided a wealth of information, and new prototypes or paradigms have shed light on future possibilities in many instances. Evidence suggests that combination and sequencing of RIT in CMRIT appropriately can provide effective treatment for many solid tumors. Vascular targets provide RIT enhancement opportunities and nanoparticles may prove to be effective carriers for RIT combined with intracellular drug delivery or alternating magnetic frequency (AMF) induced thermal tumor necrosis. The sequence and timing of combined modality treatments will be of critical importance to achieve synergy for therapy while minimizing toxicity. Fortunately, the radionuclide used for RIT also provides a signal useful for nondestructive quantitation of the influence of sequence and timing of CMRIT on events in animals and patients. This can be readily accomplished clinically using quantitative high-resolution imaging (e.g., positron emission tomography [PET])

  13. Radionuclide transport through heteogeneous media

    International Nuclear Information System (INIS)

    Hadermann, J.

    1980-01-01

    One-dimensional radionuclide migration for conevective water transport with sorption and longitudinal dispersion is investigated. A semianalytic solution for layered media with piecewise constant parametes can be written when taking into account mass conservation and approximate flux conservation at interlayer boundaries. The solution is analytic in the first layer and allows for a recursive calculation in the following layers. Scaling laws for the relevant parameters can be formulated. Numerical examples exhibit the importance of at least a single highly sorbing layer. Small values of dispersivity may not lead to a conservative estimate of conservation at the geological column's end

  14. Radionuclide transfer to meadow vegetation

    International Nuclear Information System (INIS)

    Goncharova, N.; Matsko, N.; Zhebrakova, I.; Montik, T.

    1999-01-01

    In the paper results of radioecological monitoring of natural plant populations in the 30 km zone of the Chernobyl Nuclear Power Plant (Polesky State Radioecological Reserve) during the period from 1987 to 1998 are presented. The level of radiation background in experimental areas varied from 0.1 to 30 mR/h that correspond to the total soil activity of 300-24000 kBq/m 2 (for May 1997). Monitoring was carried out including the radionuclide migration in natural plant complexes and transfer of 137 Cs between some plant organs. Refs. 3 (author)

  15. Dosimetry of incorporated transuranic radionuclides

    International Nuclear Information System (INIS)

    Loessner, V.

    1983-01-01

    Modern in vivo and in vitro techniques for detecting transuranic radionuclides within the human body are described with special emphasis on multiparameter measuring methods developed at the National Board of Nuclear Safety and Radiation Protection. Furthermore, problems related to calibration and interpretation of measuring data are discussed and new methods presented for the calculation of committed dose equivalents on the basis of data from ICRP Publication 30. Also included is an introductory chapter on radiobiological fundamentals of intake, translocation and metabolism of these nuclides. (author)

  16. Dietary intake of natural radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Smith-Briggs, J L; Bradley, E J [National Radiological Protection Board, Chilton (UK)

    1984-09-01

    The levels of the natural radionuclides, radium-226, lead-210 and polonium-210 were measured in food samples collected for a National Food Survey, thus reflecting current consumption patterns in the UK. Daily intakes of radium-226, lead-210 and inferred values of polonium-210 were calculated for 20 food groups. From these data, the annual effective dose equivalents from radium-226, lead-210 and polonium-210 in the UK diet were estimated to be 3..mu..Sv, 41..mu..Sv and 13..mu..Sv respectively.

  17. Dietary intake of natural radionuclides

    International Nuclear Information System (INIS)

    Smith-Briggs, J.L.; Bradley, E.J.

    1984-01-01

    The levels of the natural radionuclides, radium-226, lead-210 and polonium-210 were measured in food samples collected for a National Food Survey, thus reflecting current consumption patterns in the UK. Daily intakes of radium-226, lead-210 and inferred values of polonium-210 were calculated for 20 food groups. From these data, the annual effective dose equivalents from radium-226, lead-210 and polonium-210 in the UK diet were estimated to be 3μSv, 41μSv and 13μSv respectively. (U.K.)

  18. Biophysical approach to chronic kidney disease management in older patients

    Directory of Open Access Journals (Sweden)

    Alberto Foletti

    2016-06-01

    Full Text Available Chronic kidney disease (CKD and its clinical progression are a critical issue in an aging population. Therefore, strategies aimed at preventing and managing the decline of renal function are warranted. Recent evidence has provided encouraging results for the improvement of renal function achieved through an integrated biophysical approach, but prospective studies on the clinical efficacy of this strategy are still lacking. This was an open-label prospective pilot study to investigate the effect of electromagnetic information transfer through the aqueous system on kidney function of older patients affected by stage 1 or 2 CKD. Patients received biophysical therapy every 3 months over a 1-year period. Estimated glomerular filtration rate (eGFR values were calculated using the CKD–Epidemiology Collaboration formula, and were recorded at baseline and at the end of treatment. Overall, 58 patients (mean age 74.8 ± 3.7 years were included in the study. At baseline, mean eGFR was 64.6 ± 15.5 mL/min, and it significantly increased to 69.9 ± 15.8 mL/min after 1 year (+5.2 ± 10 mL/min, p<0.0002. The same trend was observed among men (+5.7 ± 10.2 mL/min, p<0.0064 and women (+4.7 ± 9.9 mL/min, p<0.014. When results were analyzed by sex, no difference was found between the 2 groups. Although further and larger prospective studies are needed, our findings suggest that an integrated biophysical approach may be feasible in the management of older patients with early-stage CKD, to reduce and prevent the decline of renal function due to aging or comorbidities.

  19. Radionuclide behavior at underground environment

    International Nuclear Information System (INIS)

    Hahn, Phil Soo; Park, Chung Kyun; Keum, Dong Kwon; Cho, Young Hwan; Kang, Moon Ja; Baik, Min Hoon; Hahn, Kyung Won; Park, Hyun Soo

    2003-04-01

    This study of radionuclide behavior at underground environment has been carried out as a part of the study of high-level waste disposal technology development. Therefore, the main objectives of this project are constructing a data-base and producing data for the safety assessment of a high-level radioactive waste, and verification of the objectivity of the assessment through characterization of the geochemical processes and experimental validation of the radionuclide migration. This project is composed of 6 subjects such as data production required for safety assessments, sorption properties and mechanisms, nuclide migration in the fractured rock, colloid formation and migration, nuclide speciation in deep geological environments, and total evaluation of geochemical behaviors considering multi-factors. The various results from the this project can be applicable to the preliminary safety and performance assessments of the established disposal concept for a future high-level radioactive waste repository. Providing required data and technical basis for assessment methodologies could be a direct application of the results. In a long-term view, the results can also be utilized as a technical background for the establishment of government policy for high-level radioactive waste disposal

  20. Radionuclide diagnostics of right ventricle

    International Nuclear Information System (INIS)

    Zaorska-Rajca, J.

    1993-01-01

    Difficulties in evaluating the right ventricle function motivate to making research into new non-invasive methods. Four radionuclide methods that are used to access the right ventricle have been discussed in this paper: first-pass angiocardiography, gated equilibrium ventriculography with red blood cells labelled in vivo technetium- 99 Tc, ventriculography with radioactive xenon 133 and a computerized single probe. Advantages and disadvantages of using each method have been discussed. RNV 99m Tc method has been recognized as the best one to evaluate RV function. Results of the right ventricle assessment in patients have been discussed in the following clinical groups: chronic cor pulmonale (CP), chronic lung disease without pulmonary arterial hypertension (LD), coronary artery disease (CAD), in patients after infarction (IMA and IMi), dilated cardiomyopathy (KZ) and valvular heart diseases (Wm and Wa). Abnormals in right ventricle function occur with different intensity in all groups, although they no specificity. The highest abnormality occurs in patients with KZ, CP, IMi and Wm, the lowest one - in patients with CAD. Abnormalities are higher in patients with congestive heart failure. In most pathological groups the right ventricle dysfunction is connected with the left ventricle insufficiency. The interdependence between the dysfunction of both ventricles is differs in particular diseases. Assessment of right ventricle function with radionuclide methods plays an important role in diagnosis and control therapy of cardiopulmonary diseases. (author). 385 refs, 48 figs, 6 tabs

  1. Stochastic approach for radionuclides quantification

    Science.gov (United States)

    Clement, A.; Saurel, N.; Perrin, G.

    2018-01-01

    Gamma spectrometry is a passive non-destructive assay used to quantify radionuclides present in more or less complex objects. Basic methods using empirical calibration with a standard in order to quantify the activity of nuclear materials by determining the calibration coefficient are useless on non-reproducible, complex and single nuclear objects such as waste packages. Package specifications as composition or geometry change from one package to another and involve a high variability of objects. Current quantification process uses numerical modelling of the measured scene with few available data such as geometry or composition. These data are density, material, screen, geometric shape, matrix composition, matrix and source distribution. Some of them are strongly dependent on package data knowledge and operator backgrounds. The French Commissariat à l'Energie Atomique (CEA) is developing a new methodology to quantify nuclear materials in waste packages and waste drums without operator adjustment and internal package configuration knowledge. This method suggests combining a global stochastic approach which uses, among others, surrogate models available to simulate the gamma attenuation behaviour, a Bayesian approach which considers conditional probability densities of problem inputs, and Markov Chains Monte Carlo algorithms (MCMC) which solve inverse problems, with gamma ray emission radionuclide spectrum, and outside dimensions of interest objects. The methodology is testing to quantify actinide activity in different kind of matrix, composition, and configuration of sources standard in terms of actinide masses, locations and distributions. Activity uncertainties are taken into account by this adjustment methodology.

  2. Infusion of radionuclides throughout pregnancy

    International Nuclear Information System (INIS)

    Mountford-Lister, P.G.; Lambert, B.E.; Milner, A.C.; Kang, X.Z.

    1992-01-01

    This work is part of a long-term study to examine the cancer incidence in the offspring of mice exposed to 239 Pu or 147 Pm throughout pregnancy. The need to model the human intake scenario and the possibility of a critical period during uterine development necessitates constant availability of radionuclides throughout pregnancy. Various methods (multiple daily injections, infusion by external cannula and infusion by indwelling osmotic pump) have been examined and osmotic infusion pumps chosen. These pumps result in a near-constant blood concentration for up to 21 days. Part of the study is the estimation of dose to the critical haemopoietic tissues of the pup from a knowledge of the radionuclide distribution and kinetics. At present the distribution has been followed from birth to 180 days. Activity in the suckling pups at 7 days old is around 1 percent of the infused activity, though most of this is accounted for by the contents of the stomach and gastrointestinal tract. The liver and femur account for around 0.025 percent and 0.012 percent respectively per pup. Activity increases in both liver and femur during lactation after which both concentration and activity fall with time. Long-term studies with the pups of dams exposed to a range of 239 Pu concentrations between 0-70 kBq/kg are underway. Correlation of average organ dose with tumour incidence will be determined at completion of the life-span study. (Author) 39 refs., 5 tabs., 6 figs

  3. Sedimentary Processes. Quantification Using Radionuclides

    International Nuclear Information System (INIS)

    Carroll, J.; Lerche, I.

    2003-01-01

    The advent of radionuclide methods in geochronology has revolutionized our understanding of modern sedimentary processes in aquatic systems. This book examines the principles of the method and its use as a quantitative tool in marine geology, with emphasis on the Pb-210 method. The assumptions and consequences of models and their behaviour are described providing the necessary background to assess the advantages and trade-offs involved when choosing a particular model for application. One of the purposes of this volume is to disentangle the influences of complicating factors, such as sediment flux variations, post-depositional diffusion of radionuclides, and bio-irrigation of sediments, to arrive at sediment ages and to properly assess the attendant data uncertainty. Environmental impacts of chemical, nuclear, or other waste material are of concern in a variety of areas around the world today. A number of relevant examples are included, demonstrating how dating models are useful for determining sources of contaminants and interpreting their influence on the environment. The book is set at a level so that an able student or professional should have no difficulty in following the procedures and methods developed. Each chapter includes case histories showing the strengths and weaknesses of a given procedure with respect to a data example. Included with this volume is the computer source code of a new generation of modelling tools based on inverse numerical analysis techniques. This first generation of the modelling tool is included, along with detailed instructions and examples for its use, in an appendix

  4. Radionuclide transit in esophageal varices

    International Nuclear Information System (INIS)

    Yeh, S.H.; Wang, S.J.; Wu, L.C.; Liu, R.S.; Tsai, Y.T.; Chiang, T.T.

    1985-01-01

    This study assessed esophageal motility in patients with esophageal varices by radionuclide transit studies. Data were acquired in list mode after an oral dose of 0.5 mCi Tc-99m sulfur colloid in 10 ml of water in the supine position above a low-energy all-purpose collimator of a gamma camera. The condensed image (CI) superimposed with a centroid curve was also produced in each case. Twenty-five normal subjects (N) and 32 patients (pts) with esophageal varices by endoscopy (large varices in Grades IV and V in 8 and small varices in Grade III or less in 24) were studied. TMTT, RTT, RF, and RI were all significantly increased in pts as compared to N. Especially, the transit time for the middle third (6.7 +- 2.6 sec vs 3.5 +- 0.9 sec in N, rho < 0.005) had the optimal sensitivy and specificity of 88% each at the cutoff value of 4.2 sec as determined by ROC analysis. In summary, radionuclide transit disorders occur in the majority of pts with esopageal varices. The middle RTT and CI are both optimal in sensitivity and specificity for detecting the abnormalities

  5. Radionuclide analysis of bush food

    International Nuclear Information System (INIS)

    Koperski, J.; Bywater, J.

    1985-01-01

    A model diet for an Aboriginal adult living entirely on bush foods collected from the Alligator Rivers Region of the Northern Territory has been established. Results of investigations of the specific activities of thorium-230, radium-226, lead-210 and polonium-210 in 123 samples of bush foods collected by Ranger Uranium Mines Pty Ltd during pre-production and production periods are presented. For all the investigated bush food items, excluding freshwater mussels (Velesunio angasi), no systematic differences were found between the specific activities of the radionuclides monitored in food items sampled during preproduction and production periods. Preliminary estimates of annual effective dose equivalent (DE) rates for stochastic effects on an adult living entirely on the model bush diet are presented. Of the four radionuclides monitored the major contributor to the effective DE rates appears to be lead-210 followed by radium-226. Among the selected nine components of the diet the major contributor to the effective DE rates appear to be mussels, water lilies and fish

  6. Radionuclide analysis of bush food

    Energy Technology Data Exchange (ETDEWEB)

    Koperski, J; Bywater, J [Ranger Uranium Mines Proprietary Ltd., Chatswood (Australia)

    1985-04-01

    A model diet for an Aboriginal adult living entirely on bush foods collected from the Alligator Rivers Region of the Northern Territory has been established. Results of investigations of the specific activities of thorium-230, radium-226, lead-210 and polonium-210 in 123 samples of bush foods collected by Ranger Uranium Mines Pty. Ltd. during pre-production and production periods are presented. For all the investigated bush food items, excluding freshwater mussels (Velesunio angasi), no systematic differences were found between the specific activities of the radionuclides monitored in food items sampled during preproduction and production periods. Preliminary estimates of annual effective dose equivalent (DE) rates for stochastic effects on an adult living entirely on the model bush diet are presented. Of the four radionuclides monitored the major contributor to the effective DE rates appears to be lead-210 followed by radium-226. Among the selected nine components of the diet the major contributor to the effective DE rates appear to be mussels, water lilies and fish.

  7. Surface enhanced raman spectroscopy analytical, biophysical and life science applications

    CERN Document Server

    Schlücker, Sebastian

    2013-01-01

    Covering everything from the basic theoretical and practical knowledge to new exciting developments in the field with a focus on analytical and life science applications, this monograph shows how to apply surface-enhanced Raman scattering (SERS) for solving real world problems. From the contents: * Theory and practice of SERS * Analytical applications * SERS combined with other analytical techniques * Biophysical applications * Life science applications including various microscopies Aimed at analytical, surface and medicinal chemists, spectroscopists, biophysicists and materials scientists. Includes a Foreword by the renowned Raman spectroscopist Professor Wolfgang Kiefer, the former Editor-in-Chief of the Journal of Raman Spectroscopy.

  8. Biophysical studies of irradiated thymocytes. 1. Surface changes

    Energy Technology Data Exchange (ETDEWEB)

    Sungurov, A Yu; Tokalov, S V; Petrov, Yu P; Sharlaeva, T M

    1985-08-15

    In order to study postirradiation changes in thymus lymphocyte surface, a number of biophysical analytical methods was used: the cell two-partition method, the physical adhesion method, fluorescence intensity and binding parameters of negatively charged ANS probe. Reduction of cell distribution factor in two-phase system and adhesion of thymocytes to cotton 1 hour after irradiation, as well as abrupt change in parameters of binding the probe in the interval of 3-4 hours after X-ray irradiation at the dose of 4 Gy are demonstrated.

  9. Short-Term Memory and Its Biophysical Model

    Science.gov (United States)

    Wang, Wei; Zhang, Kai; Tang, Xiao-wei

    1996-12-01

    The capacity of short-term memory has been studied using an integrate-and-fire neuronal network model. It is found that the storage of events depend on the manner of the correlation between the events, and the capacity is dominated by the value of after-depolarization potential. There is a monotonic increasing relationship between the value of after-depolarization potential and the memory numbers. The biophysics relevance of the network model is discussed and different kinds of the information processes are studied too.

  10. Hydrophobic ampersand hydrophilic: Theoretical models of solvation for molecular biophysics

    International Nuclear Information System (INIS)

    Pratt, L.R.; Tawa, G.J.; Hummer, G.; Garcia, A.E.; Corcelli, S.A.

    1996-01-01

    Molecular statistical thermodynamic models of hydration for chemistry and biophysics have advanced abruptly in recent years. With liquid water as solvent, salvation phenomena are classified as either hydrophobic or hydrophilic effects. Recent progress in treatment of hydrophilic effects have been motivated by continuum dielectric models interpreted as a modelistic implementation of second order perturbation theory. New results testing that perturbation theory of hydrophilic effects are presented and discussed. Recent progress in treatment of hydrophobic effects has been achieved by applying information theory to discover models of packing effects in dense liquids. The simplest models to which those ideas lead are presented and discussed

  11. Remote sensing of the Canadian Arctic: Modelling biophysical variables

    Science.gov (United States)

    Liu, Nanfeng

    It is anticipated that Arctic vegetation will respond in a variety of ways to altered temperature and precipitation patterns expected with climate change, including changes in phenology, productivity, biomass, cover and net ecosystem exchange. Remote sensing provides data and data processing methodologies for monitoring and assessing Arctic vegetation over large areas. The goal of this research was to explore the potential of hyperspectral and high spatial resolution multispectral remote sensing data for modelling two important Arctic biophysical variables: Percent Vegetation Cover (PVC) and the fraction of Absorbed Photosynthetically Active Radiation (fAPAR). A series of field experiments were conducted to collect PVC and fAPAR at three Canadian Arctic sites: (1) Sabine Peninsula, Melville Island, NU; (2) Cape Bounty Arctic Watershed Observatory (CBAWO), Melville Island, NU; and (3) Apex River Watershed (ARW), Baffin Island, NU. Linear relationships between biophysical variables and Vegetation Indices (VIs) were examined at different spatial scales using field spectra (for the Sabine Peninsula site) and high spatial resolution satellite data (for the CBAWO and ARW sites). At the Sabine Peninsula site, hyperspectral VIs exhibited a better performance for modelling PVC than multispectral VIs due to their capacity for sampling fine spectral features. The optimal hyperspectral bands were located at important spectral features observed in Arctic vegetation spectra, including leaf pigment absorption in the red wavelengths and at the red-edge, leaf water absorption in the near infrared, and leaf cellulose and lignin absorption in the shortwave infrared. At the CBAWO and ARW sites, field PVC and fAPAR exhibited strong correlations (R2 > 0.70) with the NDVI (Normalized Difference Vegetation Index) derived from high-resolution WorldView-2 data. Similarly, high spatial resolution satellite-derived fAPAR was correlated to MODIS fAPAR (R2 = 0.68), with a systematic

  12. The radionuclide migration model in river system

    International Nuclear Information System (INIS)

    Zhukova, O.M.; Shiryaeva, N.M.; Myshkina, M.K.; Shagalova, Eh.D.; Denisova, V.V.; Skurat, V.V.

    2001-01-01

    It was propose the model of radionuclide migration in river system based on principle of the compartmental model at hydraulically stationary and chemically equilibrium conditions of interaction of radionuclides in system water-dredge, water-sediments. Different conditions of radioactive contamination entry in river system were considered. The model was verified on the data of radiation monitoring of Iput' river

  13. Modeling Radionuclide Decay Chain Migration Using HYDROGEOCHEM

    Science.gov (United States)

    Lin, T. C.; Tsai, C. H.; Lai, K. H.; Chen, J. S.

    2014-12-01

    Nuclear technology has been employed for energy production for several decades. Although people receive many benefits from nuclear energy, there are inevitably environmental pollutions as well as human health threats posed by the radioactive materials releases from nuclear waste disposed in geological repositories or accidental releases of radionuclides from nuclear facilities. Theoretical studies have been undertaken to understand the transport of radionuclides in subsurface environments because that the radionuclide transport in groundwater is one of the main pathway in exposure scenarios for the intake of radionuclides. The radionuclide transport in groundwater can be predicted using analytical solution as well as numerical models. In this study, we simulate the transport of the radionuclide decay chain using HYDROGEOCHEM. The simulated results are verified against the analytical solution available in the literature. Excellent agreements between the numerical simulation and the analytical are observed for a wide spectrum of concentration. HYDROGECHEM is a useful tool assessing the ecological and environmental impact of the accidental radionuclide releases such as the Fukushima nuclear disaster where multiple radionuclides leaked through the reactor, subsequently contaminating the local groundwater and ocean seawater in the vicinity of the nuclear plant.

  14. Fire fighting in a radionuclide laboratory

    International Nuclear Information System (INIS)

    Wenzel, H.

    1991-01-01

    A fire-brigade was called to a laboratory which held a handling licence for the radionuclides C-14, T, P-32, Se-75, Mo-99, and S-35. The fire-brigade was unaware of a release of radionuclides. Therefore they used respiratory equipment, and all persons present were subsequently examined for contamination. (DG) [de

  15. Mechanisms of radionuclide transition in natural environment

    International Nuclear Information System (INIS)

    Pacyna, J.

    1974-01-01

    Mechanisms of radionuclide transition in various elements of the environment have been dealt with in an ecological aspect. The knowledge of the radionuclide propagation tracks will make possible to ascertain precisely causes and effects of the radiation and to reduce the contamination value. Particular attention has been paid to test methods. (author)

  16. Sensors and Automated Analyzers for Radionuclides

    International Nuclear Information System (INIS)

    Grate, Jay W.; Egorov, Oleg B.

    2003-01-01

    The production of nuclear weapons materials has generated large quantities of nuclear waste and significant environmental contamination. We have developed new, rapid, automated methods for determination of radionuclides using sequential injection methodologies to automate extraction chromatographic separations, with on-line flow-through scintillation counting for real time detection. This work has progressed in two main areas: radionuclide sensors for water monitoring and automated radiochemical analyzers for monitoring nuclear waste processing operations. Radionuclide sensors have been developed that collect and concentrate radionuclides in preconcentrating minicolumns with dual functionality: chemical selectivity for radionuclide capture and scintillation for signal output. These sensors can detect pertechnetate to below regulatory levels and have been engineered into a prototype for field testing. A fully automated process monitor has been developed for total technetium in nuclear waste streams. This instrument performs sample acidification, speciation adjustment, separation and detection in fifteen minutes or less

  17. Speciation of radionuclides in the environment

    International Nuclear Information System (INIS)

    Gunten, H.R. von; Benes, P.

    1994-02-01

    Methods for the determination of the speciation of radionuclides in aerosols, in aquatic solutions, in sediments, soils and rocks are reviewed. At present, most of the results about speciation are deduced from model calculations, model experiments, and separation of species (forms) of radionuclides, e.g., by sequential extraction procedures. Methods of direct determination of speciation of radionuclides (e.g. by laser induced spectroscopy) are in general not yet sensitive enough for a measurement of the very low concentrations of radionuclides in the environment. The methodological part of this paper is followed by a review of the very abundant literature about speciation of important radionuclides in the environment, i.e. in the atmosphere, hydrosphere and lithosphere. The review does not include the biosphere. Literature up to spring 1993 is included (with a few more recent additions). (author)

  18. Radionuclide transport in a single fissure

    International Nuclear Information System (INIS)

    Eriksen, T.E.

    1983-01-01

    Radionuclide migration have been studied in natural fissures orieted parallel to the axis of granite drill cores. A short pulse of the radionuclides solution was injected at one end of the fissure and the temporal change in radionuclide concentration of the eluate measured. After several hundred fissure volumes water had been pumped through the fissure following the radionuclide pulse the activity distribution on the fissure surfaces was measured. From the retardation of 152 Eu, 235 Np and 237 Pu it is concluded that these radionuclides are transported in the oxidation states Eu(III), Pu(IV) and Np(V). The distribution coefficients K sub (d) calculated from flow and activity distribution data on the basis of geometric surface area/volume ratios are of the same order as published K sub (d) values obtained from batch equilibrium experiments. (Author)

  19. Radionuclides in the environment: Risks and opportunities

    International Nuclear Information System (INIS)

    Elzerman, A.W.

    1993-01-01

    Environmental chemistry plays a critical role in the open-quotes nuclear ageclose quotes. It makes a vital contribution to understanding of the sources, fate and effects of radionuclides in the environment, both man-made and natural. Risk assessment of radionuclides in the environment relies heavily on the tools of environmental chemistry. On the other hand, radionuclides provide unique opportunities to exploit in environmental chemistry investigations due to their well-defined sources, traceability in environmental processes, analytical sensitivities, and open-quotes built-inclose quotes radioactive decay open-quotes clocksclose quotes. In some cases naturally present radionuclides are utilized, while in others tracers are deliberately added or have already been added by the nuclear fuel cycle or nuclear testing. Several examples in each of these categories are discussed to spotlight the current status of environmental chemistry and radionuclides in the environment as an example application

  20. Mobility and Bioavailability of Radionuclides in Soils

    International Nuclear Information System (INIS)

    Iurian, A.; Olufemi Phaneuf, M.; Mabit, L.

    2016-01-01

    It is crucial to understand the behavior of radionuclides in the environment, their potential mobility and bioavailability related to long-term persistence, radiological hazards, and impact on human health. Such key information is used to develop strategies that support policy decisions. The environmental behavior of radionuclides depends on ecosystem characteristics. A given soil’s capacity to immobilize radionuclides has been proved to be the main factor responsible for their resulting activity concentrations in plants. The mobility and bioavailability of radionuclides in soils is complex, depending on clay-sized soil fraction, clay mineralogy, organic matter, cation exchange capacity, pH and quantities of competing cations. Moreover, plant species have different behaviors regarding radionuclide absorption depending on soil and plan characteristics

  1. Mass spectrometry in structural biology and biophysics architecture, dynamics, and interaction of biomolecules

    CERN Document Server

    Kaltashov, Igor A; Desiderio, Dominic M; Nibbering, Nico M

    2012-01-01

    The definitive guide to mass spectrometry techniques in biology and biophysics The use of mass spectrometry (MS) to study the architecture and dynamics of proteins is increasingly common within the biophysical community, and Mass Spectrometry in Structural Biology and Biophysics: Architecture, Dynamics, and Interaction of Biomolecules, Second Edition provides readers with detailed, systematic coverage of the current state of the art. Offering an unrivalled overview of modern MS-based armamentarium that can be used to solve the most challenging problems in biophysics, structural biol

  2. Indoor Fast Neutron Generator for Biophysical and Electronic Applications

    Science.gov (United States)

    Cannuli, A.; Caccamo, M. T.; Marchese, N.; Tomarchio, E. A.; Pace, C.; Magazù, S.

    2018-05-01

    This study focuses the attention on an indoor fast neutron generator for biophysical and electronic applications. More specifically, the findings obtained by several simulations with the MCNP Monte Carlo code, necessary for the realization of a shield for indoor measurements, are presented. Furthermore, an evaluation of the neutron spectrum modification caused by the shielding is reported. Fast neutron generators are a valid and interesting available source of neutrons, increasingly employed in a wide range of research fields, such as science and engineering. The employed portable pulsed neutron source is a MP320 Thermo Scientific neutron generator, able to generate 2.5 MeV neutrons with a neutron yield of 2.0 x 106 n/s, a pulse rate of 250 Hz to 20 KHz and a duty factor varying from 5% to 100%. The neutron generator, based on Deuterium-Deuterium nuclear fusion reactions, is employed in conjunction with a solid-state photon detector, made of n-type high-purity germanium (PINS-GMX by ORTEC) and it is mainly addressed to biophysical and electronic studies. The present study showed a proposal for the realization of a shield necessary for indoor applications for MP320 neutron generator, with a particular analysis of the transport of neutrons simulated with Monte Carlo code and described the two main lines of research in which the source will be used.

  3. Biophysical influence of airborne carbon nanomaterials on natural pulmonary surfactant.

    Science.gov (United States)

    Valle, Russell P; Wu, Tony; Zuo, Yi Y

    2015-05-26

    Inhalation of nanoparticles (NP), including lightweight airborne carbonaceous nanomaterials (CNM), poses a direct and systemic health threat to those who handle them. Inhaled NP penetrate deep pulmonary structures in which they first interact with the pulmonary surfactant (PS) lining at the alveolar air-water interface. In spite of many research efforts, there is a gap of knowledge between in vitro biophysical study and in vivo inhalation toxicology since all existing biophysical models handle NP-PS interactions in the liquid phase. This technical limitation, inherent in current in vitro methodologies, makes it impossible to simulate how airborne NP deposit at the PS film and interact with it. Existing in vitro NP-PS studies using liquid-suspended particles have been shown to artificially inflate the no-observed adverse effect level of NP exposure when compared to in vivo inhalation studies and international occupational exposure limits (OELs). Here, we developed an in vitro methodology called the constrained drop surfactometer (CDS) to quantitatively study PS inhibition by airborne CNM. We show that airborne multiwalled carbon nanotubes and graphene nanoplatelets induce a concentration-dependent PS inhibition under physiologically relevant conditions. The CNM aerosol concentrations controlled in the CDS are comparable to those defined in international OELs. Development of the CDS has the potential to advance our understanding of how submicron airborne nanomaterials affect the PS lining of the lung.

  4. Single Nucleobase Identification Using Biophysical Signatures from Nanoelectronic Quantum Tunneling.

    Science.gov (United States)

    Korshoj, Lee E; Afsari, Sepideh; Khan, Sajida; Chatterjee, Anushree; Nagpal, Prashant

    2017-03-01

    Nanoelectronic DNA sequencing can provide an important alternative to sequencing-by-synthesis by reducing sample preparation time, cost, and complexity as a high-throughput next-generation technique with accurate single-molecule identification. However, sample noise and signature overlap continue to prevent high-resolution and accurate sequencing results. Probing the molecular orbitals of chemically distinct DNA nucleobases offers a path for facile sequence identification, but molecular entropy (from nucleotide conformations) makes such identification difficult when relying only on the energies of lowest-unoccupied and highest-occupied molecular orbitals (LUMO and HOMO). Here, nine biophysical parameters are developed to better characterize molecular orbitals of individual nucleobases, intended for single-molecule DNA sequencing using quantum tunneling of charges. For this analysis, theoretical models for quantum tunneling are combined with transition voltage spectroscopy to obtain measurable parameters unique to the molecule within an electronic junction. Scanning tunneling spectroscopy is then used to measure these nine biophysical parameters for DNA nucleotides, and a modified machine learning algorithm identified nucleobases. The new parameters significantly improve base calling over merely using LUMO and HOMO frontier orbital energies. Furthermore, high accuracies for identifying DNA nucleobases were observed at different pH conditions. These results have significant implications for developing a robust and accurate high-throughput nanoelectronic DNA sequencing technique. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Assimilation of Biophysical Neuronal Dynamics in Neuromorphic VLSI.

    Science.gov (United States)

    Wang, Jun; Breen, Daniel; Akinin, Abraham; Broccard, Frederic; Abarbanel, Henry D I; Cauwenberghs, Gert

    2017-12-01

    Representing the biophysics of neuronal dynamics and behavior offers a principled analysis-by-synthesis approach toward understanding mechanisms of nervous system functions. We report on a set of procedures assimilating and emulating neurobiological data on a neuromorphic very large scale integrated (VLSI) circuit. The analog VLSI chip, NeuroDyn, features 384 digitally programmable parameters specifying for 4 generalized Hodgkin-Huxley neurons coupled through 12 conductance-based chemical synapses. The parameters also describe reversal potentials, maximal conductances, and spline regressed kinetic functions for ion channel gating variables. In one set of experiments, we assimilated membrane potential recorded from one of the neurons on the chip to the model structure upon which NeuroDyn was designed using the known current input sequence. We arrived at the programmed parameters except for model errors due to analog imperfections in the chip fabrication. In a related set of experiments, we replicated songbird individual neuron dynamics on NeuroDyn by estimating and configuring parameters extracted using data assimilation from intracellular neural recordings. Faithful emulation of detailed biophysical neural dynamics will enable the use of NeuroDyn as a tool to probe electrical and molecular properties of functional neural circuits. Neuroscience applications include studying the relationship between molecular properties of neurons and the emergence of different spike patterns or different brain behaviors. Clinical applications include studying and predicting effects of neuromodulators or neurodegenerative diseases on ion channel kinetics.

  6. Quantum-Sequencing: Biophysics of quantum tunneling through nucleic acids

    Science.gov (United States)

    Casamada Ribot, Josep; Chatterjee, Anushree; Nagpal, Prashant

    2014-03-01

    Tunneling microscopy and spectroscopy has extensively been used in physical surface sciences to study quantum tunneling to measure electronic local density of states of nanomaterials and to characterize adsorbed species. Quantum-Sequencing (Q-Seq) is a new method based on tunneling microscopy for electronic sequencing of single molecule of nucleic acids. A major goal of third-generation sequencing technologies is to develop a fast, reliable, enzyme-free single-molecule sequencing method. Here, we present the unique ``electronic fingerprints'' for all nucleotides on DNA and RNA using Q-Seq along their intrinsic biophysical parameters. We have analyzed tunneling spectra for the nucleotides at different pH conditions and analyzed the HOMO, LUMO and energy gap for all of them. In addition we show a number of biophysical parameters to further characterize all nucleobases (electron and hole transition voltage and energy barriers). These results highlight the robustness of Q-Seq as a technique for next-generation sequencing.

  7. Biophysical basis for the geometry of conical stromatolites.

    Science.gov (United States)

    Petroff, Alexander P; Sim, Min Sub; Maslov, Andrey; Krupenin, Mikhail; Rothman, Daniel H; Bosak, Tanja

    2010-06-01

    Stromatolites may be Earth's oldest macroscopic fossils; however, it remains controversial what, if any, biological processes are recorded in their morphology. Although the biological interpretation of many stromatolite morphologies is confounded by the influence of sedimentation, conical stromatolites form in the absence of sedimentation and are, therefore, considered to be the most robust records of biophysical processes. A qualitative similarity between conical stromatolites and some modern microbial mats suggests a photosynthetic origin for ancient stromatolites. To better understand and interpret ancient fossils, we seek a quantitative relationship between the geometry of conical stromatolites and the biophysical processes that control their growth. We note that all modern conical stromatolites and many that formed in the last 2.8 billion years display a characteristic centimeter-scale spacing between neighboring structures. To understand this prominent-but hitherto uninterpreted-organization, we consider the role of diffusion in mediating competition between stromatolites. Having confirmed this model through laboratory experiments and field observation, we find that organization of a field of stromatolites is set by a diffusive time scale over which individual structures compete for nutrients, thus linking form to physiology. The centimeter-scale spacing between modern and ancient stromatolites corresponds to a rhythmically fluctuating metabolism with a period of approximately 20 hr. The correspondence between the observed spacing and the day length provides quantitative support for the photosynthetic origin of conical stromatolites throughout geologic time.

  8. Developing a physics expert identity in a biophysics research group

    Science.gov (United States)

    Rodriguez, Idaykis; Goertzen, Renee Michelle; Brewe, Eric; Kramer, Laird H.

    2015-06-01

    We investigate the development of expert identities through the use of the sociocultural perspective of learning as participating in a community of practice. An ethnographic case study of biophysics graduate students focuses on the experiences the students have in their research group meetings. The analysis illustrates how the communities of practice-based identity constructs of competencies characterize student expert membership. A microanalysis of speech, sound, tones, and gestures in video data characterize students' social competencies in the physics community of practice. Results provide evidence that students at different stages of their individual projects have opportunities to develop social competencies such as mutual engagement, negotiability of the repertoire, and accountability to the enterprises as they interact with group members. The biophysics research group purposefully designed a learning trajectory including conducting research and writing it for publication in the larger community of practice as a pathway to expertise. The students of the research group learn to become socially competent as specific experts of their project topic and methodology, ensuring acceptance, agency, and membership in their community of practice. This work expands research on physics expertise beyond the cognitive realm and has implications for how to design graduate learning experiences to promote expert identity development.

  9. Biophysics of filament length regulation by molecular motors

    International Nuclear Information System (INIS)

    Kuan, Hui-Shun; Betterton, M D

    2013-01-01

    Regulating physical size is an essential problem that biological organisms must solve from the subcellular to the organismal scales, but it is not well understood what physical principles and mechanisms organisms use to sense and regulate their size. Any biophysical size-regulation scheme operates in a noisy environment and must be robust to other cellular dynamics and fluctuations. This work develops theory of filament length regulation inspired by recent experiments on kinesin-8 motor proteins, which move with directional bias on microtubule filaments and alter microtubule dynamics. Purified kinesin-8 motors can depolymerize chemically-stabilized microtubules. In the length-dependent depolymerization model, the rate of depolymerization tends to increase with filament length, because long filaments accumulate more motors at their tips and therefore shorten more quickly. When balanced with a constant filament growth rate, this mechanism can lead to a fixed polymer length. However, the mechanism by which kinesin-8 motors affect the length of dynamic microtubules in cells is less clear. We study the more biologically realistic problem of microtubule dynamic instability modulated by a motor-dependent increase in the filament catastrophe frequency. This leads to a significant decrease in the mean filament length and a narrowing of the filament length distribution. The results improve our understanding of the biophysics of length regulation in cells. (paper)

  10. Climate Change Effects on Agriculture: Economic Responses to Biophysical Shocks

    Science.gov (United States)

    Nelson, Gerald C.; Valin, Hugo; Sands, Ronald D.; Havlik, Petr; Ahammad, Helal; Deryng, Delphine; Elliott, Joshua; Fujimori, Shinichiro; Hasegawa, Tomoko; Heyhoe, Edwina

    2014-01-01

    Agricultural production is sensitive to weather and thus directly affected by climate change. Plausible estimates of these climate change impacts require combined use of climate, crop, and economic models. Results from previous studies vary substantially due to differences in models, scenarios, and data. This paper is part of a collective effort to systematically integrate these three types of models. We focus on the economic component of the assessment, investigating how nine global economic models of agriculture represent endogenous responses to seven standardized climate change scenarios produced by two climate and five crop models. These responses include adjustments in yields, area, consumption, and international trade. We apply biophysical shocks derived from the Intergovernmental Panel on Climate Change's representative concentration pathway with end-of-century radiative forcing of 8.5 W/m(sup 2). The mean biophysical yield effect with no incremental CO2 fertilization is a 17% reduction globally by 2050 relative to a scenario with unchanging climate. Endogenous economic responses reduce yield loss to 11%, increase area of major crops by 11%, and reduce consumption by 3%. Agricultural production, cropland area, trade, and prices show the greatest degree of variability in response to climate change, and consumption the lowest. The sources of these differences include model structure and specification; in particular, model assumptions about ease of land use conversion, intensification, and trade. This study identifies where models disagree on the relative responses to climate shocks and highlights research activities needed to improve the representation of agricultural adaptation responses to climate change.

  11. Biophysical aspects of using liposomes as delivery vehicles.

    Science.gov (United States)

    Ulrich, Anne S

    2002-04-01

    Liposomes are used as biocompatible carriers of drugs, peptides, proteins, plasmic DNA, antisense oligonucleotides or ribozymes, for pharmaceutical, cosmetic, and biochemical purposes. The enormous versatility in particle size and in the physical parameters of the lipids affords an attractive potential for constructing tailor-made vehicles for a wide range of applications. Some of the recent literature will be reviewed here and presented from a biophysical point of view, thus providing a background for the more specialized articles in this special issue on liposome technology. Different properties (size, colloidal behavior, phase transitions, and polymorphism) of diverse lipid formulations (liposomes, lipoplexes, cubic phases, emulsions, and solid lipid nanoparticles) for distinct applications (parenteral, transdermal, pulmonary, and oral administration) will be rationalized in terms of common structural, thermodynamic and kinetic parameters of the lipids. This general biophysical basis helps to understand pharmaceutically relevant aspects such as liposome stability during storage and towards serum, the biodistribution and specific targeting of cargo, and how to trigger drug release and membrane fusion. Methods for the preparation and characterization of liposomal formulations in vitro will be outlined, too.

  12. Radionuclide imaging of spinal infections

    International Nuclear Information System (INIS)

    Gemmel, Filip; Dumarey, Nicolas; Palestro, Christopher J.

    2006-01-01

    The diagnosis of spinal infection, with or without implants, has been a challenge for physicians for many years. Spinal infections are now being recognised more frequently, owing to aging of the population and the increasing use of spinal-fusion surgery. The diagnosis in many cases is delayed, and this may result in permanent neurological damage or even death. Laboratory evidence of infection is variable. Conventional radiography and radionuclide bone imaging lack both sensitivity and specificity. Neither in vitro labelled leucocyte scintigraphy nor 99m Tc-anti-granulocyte antibody scintigraphy is especially useful, because of the frequency with which spinal infection presents as a non-specific photopenic area on these tests. Sequential bone/gallium imaging and 67 Ga-SPECT are currently the radionuclide procedures of choice for spinal osteomyelitis, but these tests lack specificity, suffer from poor spatial resolution and require several days to complete. [ 18 F]Fluoro-2-deoxy-D-glucose (FDG) PET is a promising technique for diagnosing spinal infection, and has several potential advantages over conventional radionuclide tests. The study is sensitive and is completed in a single session, and image quality is superior to that obtained with single-photon emitting tracers. The specificity of FDG-PET may also be superior to that of conventional tracers because degenerative bone disease and fractures usually do not produce intense FDG uptake; moreover, spinal implants do not affect FDG imaging. However, FDG-PET images have to be read with caution in patients with instrumented spinal-fusion surgery since non-specific accumulation of FDG around the fusion material is not uncommon. In the future, PET-CT will likely provide more precise localisation of abnormalities. FDG-PET may prove to be useful for monitoring response to treatment in patients with spinal osteomyelitis. Other tracers for diagnosing spinal osteomyelitis are also under investigation, including radiolabelled

  13. Radionuclide imaging of spinal infections

    Energy Technology Data Exchange (ETDEWEB)

    Gemmel, Filip [Ghent Maria-Middelares, General Hospital, Division of Nuclear Medicine, Ghent (Belgium); Medical Center Leeuwarden (MCL), Division of Nuclear Medicine, Henri Dunantweg 2, Postbus 888, Leeuwarden (Netherlands); Dumarey, Nicolas [Universite Libre de Bruxelles, Hopital Erasme, Division of Nuclear Medicine, Brussels (Belgium); Palestro, Christopher J. [Long Island Jewish Medical Center, Division of Nuclear Medicine, Long Island, NY (United States)

    2006-10-15

    The diagnosis of spinal infection, with or without implants, has been a challenge for physicians for many years. Spinal infections are now being recognised more frequently, owing to aging of the population and the increasing use of spinal-fusion surgery. The diagnosis in many cases is delayed, and this may result in permanent neurological damage or even death. Laboratory evidence of infection is variable. Conventional radiography and radionuclide bone imaging lack both sensitivity and specificity. Neither in vitro labelled leucocyte scintigraphy nor {sup 99m}Tc-anti-granulocyte antibody scintigraphy is especially useful, because of the frequency with which spinal infection presents as a non-specific photopenic area on these tests. Sequential bone/gallium imaging and {sup 67}Ga-SPECT are currently the radionuclide procedures of choice for spinal osteomyelitis, but these tests lack specificity, suffer from poor spatial resolution and require several days to complete. [{sup 18}F]Fluoro-2-deoxy-D-glucose (FDG) PET is a promising technique for diagnosing spinal infection, and has several potential advantages over conventional radionuclide tests. The study is sensitive and is completed in a single session, and image quality is superior to that obtained with single-photon emitting tracers. The specificity of FDG-PET may also be superior to that of conventional tracers because degenerative bone disease and fractures usually do not produce intense FDG uptake; moreover, spinal implants do not affect FDG imaging. However, FDG-PET images have to be read with caution in patients with instrumented spinal-fusion surgery since non-specific accumulation of FDG around the fusion material is not uncommon. In the future, PET-CT will likely provide more precise localisation of abnormalities. FDG-PET may prove to be useful for monitoring response to treatment in patients with spinal osteomyelitis. Other tracers for diagnosing spinal osteomyelitis are also under investigation, including

  14. Social and Biophysical Predictors of Public Perceptions of Extreme Fires

    Science.gov (United States)

    Hall, T. E.; Kooistra, C. M.; Paveglio, T.; Gress, S.; Smith, A. M.

    2013-12-01

    To date, what constitutes an 'extreme' fire has been approached separately by biophysical and social scientists. Research on the biophysical characteristics of fires has identified potential dimensions of extremity, including fire size and vegetation mortality. On the social side, factors such as the degree of immediate impact to one's life and property or the extent of social disruption in the community contribute to a perception of extremity. However, some biophysical characteristics may also contribute to perceptions of extremity, including number of simultaneous ignitions, rapidity of fire spread, atypical fire behavior, and intensity of smoke. Perceptions of these impacts can vary within and across communities, but no studies to date have investigated such perceptions in a comprehensive way. In this study, we address the question, to what extent is the magnitude of impact of fires on WUI residents' well-being explained by measurable biophysical characteristics of the fire and subjective evaluations of the personal and community-level impacts of the fire? We bring together diverse strands of psychological theory, including landscape perception, mental models, risk perception, and community studies. The majority of social science research on fires has been in the form of qualitative case studies, and our study is methodologically unique by using a nested design (hierarchical modeling) to enable generalizable conclusions across a wide range of fires and human communities. We identified fires that burned in 2011 or 2012 in the northern Rocky Mountain region that were at least 1,000 acres and that intersected (within 15 km) urban clusters or identified Census places. For fires where an adequately large number of households was located in proximity to the fire, we drew random samples of approximately 150 individuals for each fire. We used a hybrid internet (Qualtrics) and mail survey, following the Dillman method, to measure individual perceptions. We developed two

  15. Understanding the biophysical effects of transcranial magnetic stimulation on brain tissue: the bridge between brain stimulation and cognition.

    Science.gov (United States)

    Neggers, Sebastiaan F W; Petrov, Petar I; Mandija, Stefano; Sommer, Iris E C; van den Berg, Nico A T

    2015-01-01

    Transcranial magnetic stimulation (TMS) is rapidly being adopted in neuroscience, medicine, psychology, and biology, for basic research purposes, diagnosis, and therapy. However, a coherent picture of how TMS affects neuronal processing, and especially how this in turn influences behavior, is still largely unavailable despite several studies that investigated aspects of the underlying neurophysiological effects of TMS. Perhaps as a result from this "black box approach," TMS studies show a large interindividual variability in applied paradigms and TMS treatment outcome can be quite variable, hampering its general efficacy and introduction into the clinic. A better insight into the biophysical, neuronal, and cognitive mechanisms underlying TMS is crucial in order to apply it effectively in the clinic and to increase our understanding of brain-behavior relationship. Therefore, computational and experimental efforts have been started recently to understand and control the effect TMS has on neuronal functioning. Especially, how the brain shapes magnetic fields induced by a TMS coil, how currents are generated locally in the cortical surface, and how they interact with complex functional neuronal circuits within and between brain areas are crucial to understand the observed behavioral changes and potential therapeutic effects resulting from TMS. Here, we review the current knowledge about the biophysical underpinnings of single-pulse TMS and argue how to move forward to fully understand and exploit the powerful technique that TMS can be. © 2015 Elsevier B.V. All rights reserved.

  16. Radionuclide interactions with marine sediments

    International Nuclear Information System (INIS)

    Higgo, J.J.W.

    1987-09-01

    A critical review of the literature on the subject of the interactions of radionuclides with marine sediments has been carried out. On the basis of the information available, an attempt has been made to give ranges and 'best estimates' for the distribution ratios between seawater and sediments. These estimates have been based on an understanding of the sediment seawater system and the porewater chemistry and mineralogy. Field measurements, laboratory measurements and estimates based on stable-element geochemical data are all taken into account. Laboratory measurements include distribution-ratio and diffusion-coefficient determinations. The elements reviewed are carbon, chlorine, calcium, nickel, selenium, strontium, zirconium, niobium, technetium, tin, iodine, caesium, lead, radium, actinium, thorium, protactinium, uranium, neptunium, plutonium, americium and curium. (author)

  17. Expert system based radionuclide identification

    International Nuclear Information System (INIS)

    Aarnio, P.A.; Ala-Heikkil, J.J.; Hakulinen, T.T.; Nikkinen, M.T.

    1998-01-01

    An expert system coupled with the gamma spectrum analysis system SAMPO has been developed for automating the qualitative identification of radionuclides as well as for determining the quantitative parameters of the spectrum components. The program is written in C-language and runs in various environments ranging from PCs to UNIX workstations. The expert system utilizes a complete gamma library with over 2600 nuclides and 80,000 lines, and a rule base of about fifty criteria including energies, relative peak intensities, genesis modes, half lives, parent-daughter relationships, etc. The rule base is furthermore extensible by the user. This is not an original contribution but a somewhat updated version of papers and reports previously published elsewhere. (author)

  18. Radionuclide diagnosis of allograft rejection

    International Nuclear Information System (INIS)

    George, E.A.

    1982-01-01

    Interaction with one or more anatomical and physiopathological characteristics of the rejecting renal allograft is suggested by those radioagents utilized specifically for the diagnosis of allograft rejection. Rejection, the most common cause of declining allograft function, is frequently mimicked clinically or masked by other immediate or long term post transplant complications. Understanding of the anatomical pathological features and kinetics of rejection and their modification by immunosuppressive maintenance and therapy are important for the proper clinical utilization of these radioagents. Furthermore, in selecting these radionuclides, one has to consider the comparative availability, preparatory and procedural simplicity, acquisition and display techniques and the possibility of timely report. The clinical utilities of radiofibrinogen, /sup 99m/Tc sulfur colloid and 67 Ga in the diagnosis of allograft rejection have been evaluated to a variable extent in the past. The potential usefulness of the recently developed preparations of 111 In labeled autologous leukocytes and platelets are presently under investigation

  19. Quality assurance in radionuclide laboratories

    International Nuclear Information System (INIS)

    Otto, R.; Voelkle, H.; Wershofen, H.; Wilhelm, C.

    2003-01-01

    The authors are members of an ad-hoc working group preparing a contribution to the procedures manual (''Loseblattsammlung'') dealing with quality assurance and quality control in radionuclide laboratories. The Loseblattsammlung is edited by the working group ''Environmental Monitoring'' of the German-Swiss Radiological Protection Association. The intention of the manual under preparation is not to give a procedure on how to establish a quality management system allowing for an accreditation in accordance with the international standard DIN EN ISO/IEC 17025:2000 04 (''ISO 17025'') [1] but to compile routine quality control procedures necessary for reliable measurements and to give tips to the practitioner on how to keep both the extent and the frequency of procedures on a reasonable level. A short version of the Loseblatt is presented here. (orig.)

  20. Placental transfer of other radionuclides

    International Nuclear Information System (INIS)

    Stieve, F.-E.

    1987-01-01

    This paper comments upon some basic principles of the transfer of radioactive substances in human beings to the embryo and fetus and their age-dependence. These principles may apply to the main effects currently known from the uptake, accumulation, retention and excretion of those radioactive substances, which may be of special interest in assessing the dose and therefore the risk of exposure in nuclear medicine, in connection with environmental problems of nuclear power production as well as nuclear explosions. As an example the age-dependence of several typical radionuclides and their age-dependence during the development of the human embryo and fetus and its correlation to observations on several animal species are presented. 30 refs.; 5 figs

  1. Transverse section radionuclide scanning system

    International Nuclear Information System (INIS)

    Kuhl, D.E.; Edwards, R.Q.

    1976-01-01

    This invention provides a transverse section radionuclide scanning system for high-sensitivity quantification of brain radioactivity in cross-section picture format in order to permit accurate assessment of regional brain function localized in three dimensions. High sensitivity crucially depends on overcoming the heretofore known raster type scanning, which requires back and forth detector movement involving dead-time or partial enclosure of the scan field. Accordingly, this invention provides a detector array having no back and forth movement by interlaced detectors that enclose the scan field and rotate as an integral unit around one axis of rotation in a slip ring that continuously transmits the detector data by means of laser emitting diodes, with the advantages that increased amounts of data can be continuously collected, processed and displayed with increased sensitivity according to a suitable computer program. 5 claims, 11 figures

  2. Radionuclide evaluation of brain death

    International Nuclear Information System (INIS)

    Pjura, G.A.; Kim, E.E.

    1987-01-01

    The criteria employed for clinical determination of death have evolved in response to advances in life support and other medical technology. The technical feasibility of organ transplantation has amplified the need for a definition of brain death that can be applied in the shortest possible time in the presence of artificial maintenance of vegetative functions, including circulation. Radionuclide cerebral angiography is one of a group of diagnostic procedures that can be employed to confirm the clinical diagnosis of brain death through demonstration of absence of cerebral blood flow. The focus of this work is to assess its use as a confirmatory test for determination of brain death in the context of currently available alternative technologies

  3. Radionuclide diagnosis of vasculogenic impotence

    International Nuclear Information System (INIS)

    Sorokin, A.I.; Gerasimov, V.G.; Lenskaya, O.P.; Narkevich, B.Ya.; Bogdasarov, Yu.B.; Krotovskij, G.S.

    1988-01-01

    Pathogenesis of vasculogenic impotence is most adequately revealed by modern methods of the investigation of the hemodynamic mechanisms of erection with the enhancement of arterial perfusion of corpora cavernosa by artificial sexual stimulation. Radionuclide diagnostic methods effectively differ from the methods of radiocontrast phalloangiography by the simplicity of investigation and the absence of traumatism for a patient. The authors have proposed a mathematical model of a process of filling in the functioning volume of the penile vascular bed with a radiopharmaceutical prepation against the background of erection induced by intracavernous administration of papaverine hydrochloride solution. Parameters of the model determine the ratio of blood flow volumetric rates in the penis at rest and when erect

  4. Decontamination of radionuclides in food

    Energy Technology Data Exchange (ETDEWEB)

    Ohmomo, Yoichiro [Institute for Environmental Sciences, Aomori (Japan)

    1994-03-01

    The release of radionuclides arising from the Chernobyle accident led to widespread contamination of the northern hemisphere through fallout. This accident provided again an opportunity to investigate how and to what extent the radionuclides contamination in crops and animal derived foods could be reduced. The following topics are included in this paper. (1) How to reduce the transfer of radiostrontium and/or cesium from soil to crops: A pH increase of soil is effective for reducing their plant uptake. (2) How to reduce the transfer of radiocesium to animal derived foods: Ammonium-ferric-cyanoferrate (AFCF) should be the most effective compound for radiocesium excretion in the feces. Experiments with lactating cows and/or poultry gave extremely good results with respect to low radiocesium concentrations in milk, meat and eggs. (3) Removal coefficients of radiostrontium, cesium and iodine from contaminated leaf vegetables and cereals during food processing and culinary preparation: Though different by species, more than 80% of cesium and about 50% of strontium and iodine can be removed during culinary preparation of washing and boiling. (4) Simultaneous decontamination of radiocesium and iodine from drinking water and liquid milk: Metal ferrocyanide-anion exchange resin, specifically Fe ferrocyanide one, was successfully used for a rapid and simple decontamination of radiocesium and iodine in the liquid samples arising from the Chernobyle accident. (5) Removal of radiocesium from meat: The meat structurally contaminated with radiocesium is easily and very successfully decontaminated by pickling in NaCl solution and the decontamination is much speeded up by freezing meat before pickling. (author).

  5. Illicit Trafficking of Natural Radionuclides

    International Nuclear Information System (INIS)

    Friedrich, Steinhaeusler; Lyudmila, Zaitseva

    2008-01-01

    Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium ( 20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from an operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s); (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces

  6. Illicit Trafficking of Natural Radionuclides

    Science.gov (United States)

    Friedrich, Steinhäusler; Lyudmila, Zaitseva

    2008-08-01

    Natural radionuclides have been subject to trafficking worldwide, involving natural uranium ore (U 238), processed uranium (yellow cake), low enriched uranium (20% U 235), radium (Ra 226), polonium (Po 210), and natural thorium ore (Th 232). An important prerequisite to successful illicit trafficking activities is access to a suitable logistical infrastructure enabling an undercover shipment of radioactive materials and, in case of trafficking natural uranium or thorium ore, capable of transporting large volumes of material. Covert en route diversion of an authorised uranium transport, together with covert diversion of uranium concentrate from an operating or closed uranium mines or mills, are subject of case studies. Such cases, involving Israel, Iran, Pakistan and Libya, have been analyzed in terms of international actors involved and methods deployed. Using international incident data contained in the Database on Nuclear Smuggling, Theft and Orphan Radiation Sources (DSTO) and international experience gained from the fight against drug trafficking, a generic Trafficking Pathway Model (TPM) is developed for trafficking of natural radionuclides. The TPM covers the complete trafficking cycle, ranging from material diversion, covert material transport, material concealment, and all associated operational procedures. The model subdivides the trafficking cycle into five phases: (1) Material diversion by insider(s) or initiation by outsider(s); (2) Covert transport; (3) Material brokerage; (4) Material sale; (5) Material delivery. An Action Plan is recommended, addressing the strengthening of the national infrastructure for material protection and accounting, development of higher standards of good governance, and needs for improving the control system deployed by customs, border guards and security forces.

  7. Decontamination of radionuclides in food

    International Nuclear Information System (INIS)

    Ohmomo, Yoichiro

    1994-01-01

    The release of radionuclides arising from the Chernobyle accident led to widespread contamination of the northern hemisphere through fallout. This accident provided again an opportunity to investigate how and to what extent the radionuclides contamination in crops and animal derived foods could be reduced. The following topics are included in this paper. (1) How to reduce the transfer of radiostrontium and/or cesium from soil to crops: A pH increase of soil is effective for reducing their plant uptake. (2) How to reduce the transfer of radiocesium to animal derived foods: Ammonium-ferric-cyanoferrate (AFCF) should be the most effective compound for radiocesium excretion in the feces. Experiments with lactating cows and/or poultry gave extremely good results with respect to low radiocesium concentrations in milk, meat and eggs. (3) Removal coefficients of radiostrontium, cesium and iodine from contaminated leaf vegetables and cereals during food processing and culinary preparation: Though different by species, more than 80% of cesium and about 50% of strontium and iodine can be removed during culinary preparation of washing and boiling. (4) Simultaneous decontamination of radiocesium and iodine from drinking water and liquid milk: Metal ferrocyanide-anion exchange resin, specifically Fe ferrocyanide one, was successfully used for a rapid and simple decontamination of radiocesium and iodine in the liquid samples arising from the Chernobyle accident. (5) Removal of radiocesium from meat: The meat structurally contaminated with radiocesium is easily and very successfully decontaminated by pickling in NaCl solution and the decontamination is much speeded up by freezing meat before pickling. (author)

  8. Investigating Irregularly Patterned Deep Brain Stimulation Signal Design Using Biophysical Models

    Directory of Open Access Journals (Sweden)

    Samantha Rose Summerson

    2015-06-01

    Full Text Available Parkinson’s disease (PD is a neurodegenerative disorder which follows from cell loss of dopaminergic neurons in the substantia nigra pars compacta (SNc, a nucleus in the basal ganglia (BG. Deep brain stimulation (DBS is an electrical therapy that modulates the pathological activity to treat the motor symptoms of PD. Although this therapy is currently used in clinical practice, the sufficient conditions for therapeutic efficacy are unknown. In this work we develop a model of critical motor circuit structures in the brain using biophysical cell models as the base components and then evaluate performance of different DBS signals in this model to perform comparative studies of their efficacy. Biological models are an important tool for gaining insights into neural function and, in this case, serve as effective tools for investigating innovative new DBS paradigms. Experiments were performed using the hemi-parkinsonian rodent model to test the same set of signals, verifying the obedience of the model to physiological trends. We show that antidromic spiking from DBS of the subthalamic nucleus (STN has a significant impact on cortical neural activity, which is frequency dependent and additionally modulated by the regularity of the stimulus pulse train used. Irregular spacing between stimulus pulses, where the amount of variability added is bounded, is shown to increase diversification of response of basal ganglia neurons and reduce entropic noise in cortical neurons, which may be fundamentally important to restoration of information flow in the motor circuit.

  9. Molecular, biophysical, and pharmacological properties of calcium-activated chloride channels.

    Science.gov (United States)

    Kamaleddin, Mohammad Amin

    2018-02-01

    Calcium-activated chloride channels (CaCCs) are a family of anionic transmembrane ion channels. They are mainly responsible for the movement of Cl - and other anions across the biological membranes, and they are widely expressed in different tissues. Since the Cl - flow into or out of the cell plays a crucial role in hyperpolarizing or depolarizing the cells, respectively, the impact of intracellular Ca 2+ concentration on these channels is attracting a lot of attentions. After summarizing the molecular, biophysical, and pharmacological properties of CaCCs, the role of CaCCs in normal cellular functions will be discussed, and I will emphasize how dysregulation of CaCCs in pathological conditions can account for different diseases. A better understanding of CaCCs and a pivotal regulatory role of Ca 2+ can shed more light on the therapeutic strategies for different neurological disorders that arise from chloride dysregulation, such as asthma, cystic fibrosis, and neuropathic pain. © 2017 Wiley Periodicals, Inc.

  10. Report of the consultants' meeting on target and processing technologies for cyclotron production of radionuclides

    International Nuclear Information System (INIS)

    1999-11-01

    is not widely available. New target technology could make this radionuclide available from even low energy cyclotrons. The same technology can be applied to the production of I-124, which is a PET radionuclide, which also has potential as a therapeutic agent. Pd-103 has become an extremely important radionuclide for the treatment of prostate cancer when incorporated into sealed sources. The target preparation technology requires further research including the chemical processing of the target materials. The entire above target systems use either enriched or very expensive target materials thus the importance of target recover procedures is recognised. This technology has direct application in other target systems

  11. Human dose pathways of radionuclides in forests

    International Nuclear Information System (INIS)

    Rantavaara, A.

    2009-01-01

    Forest soil, understorey vegetation and trees are all sources of radionuclides and human radiation doses after contaminating atmospheric deposition. People are exposed to radiation externally from sources outside the body and internally via ingestion and inhalation of radionuclides. Understorey vegetation contributes to ingestion doses through berries, herbs, wild honey, mushrooms and game meat; also trees provide feed to terrestrial birds and big game. During stay in forests people are subject to external radiation from forest floor and overstorey, and they may inhale airborne radioactive aerosol or gaseous radionuclides in ground level air. In the early phase of contamination also resuspended radionuclides may add to the internal dose of people via inhalation. People in Nordic countries are most exposed to radiation via ingestion of radionuclides in wild foods. The distribution of radionuclides in forests is changed by environmental processes, and thereby also the significance of various dose pathways to humans will change with time. External exposure is received in living environment from contaminated stemwood used as building timber and for manufacturing of furniture and other wood products. The aim of this paper is to outline the significance of various human dose pathways of radionuclides in forests considering the public and workers in forestry and production of bioenergy. Examples on effective doses are given based on two historical events, atmospheric nuclear weapon tests (mostly in 1950's and in 1960's) and the Chernobyl nuclear power plant accident in 1986. (au)

  12. Radionuclides: Accumulation and Transport in Plants.

    Science.gov (United States)

    Gupta, D K; Chatterjee, S; Datta, S; Voronina, A V; Walther, C

    Application of radioactive elements or radionuclides for anthropogenic use is a widespread phenomenon nowadays. Radionuclides undergo radioactive decays releasing ionizing radiation like gamma ray(s) and/or alpha or beta particles that can displace electrons in the living matter (like in DNA) and disturb its function. Radionuclides are highly hazardous pollutants of considerable impact on the environment, food chain and human health. Cleaning up of the contaminated environment through plants is a promising technology where the rhizosphere may play an important role. Plants belonging to the families of Brassicaceae, Papilionaceae, Caryophyllaceae, Poaceae, and Asteraceae are most important in this respect and offer the largest potential for heavy metal phytoremediation. Plants like Lactuca sativa L., Silybum marianum Gaertn., Centaurea cyanus L., Carthamus tinctorius L., Helianthus annuus and H. tuberosus are also important plants for heavy metal phytoremediation. However, transfer factors (TF) of radionuclide from soil/water to plant ([Radionuclide]plant/[Radionuclide]soil) vary widely in different plants. Rhizosphere, rhizobacteria and varied metal transporters like NRAMP, ZIP families CDF, ATPases (HMAs) family like P1B-ATPases, are involved in the radio-phytoremediation processes. This review will discuss recent advancements and potential application of plants for radionuclide removal from the environment.

  13. Radionuclides in air, water, and biota

    International Nuclear Information System (INIS)

    Seymour, A.H.; Nelson, V.A.

    1977-01-01

    Air, water, and biological samples collected before and after the 1965, 1969, and 1971 underground nuclear detonations at Amchitka Island were analyzed for natural and fallout radionuclides by gamma spectrometry. Selected samples were also analyzed for tritium, 55 Fe, and 90 Sr. The objectives were to search for and identify radionuclides of Amchitka origin in the samples and to contribute to the general knowledge of the distribution of radionuclides in the environment. The studies showed that there has been no escape of radionuclides from the underground sites of the three nuclear detonations at Amchitka Island except for trace quantities of radionuclides, principally tritium, in water and soil gas samples from the immediate vicinity of the surface ground zero for the 1965 event. Two naturally occurring radionuclides, 40 K and 7 Be, were the most abundant radionuclides in the samples, usually by a factor of 10 or more, except for 137 Cs in lichen samples. All levels were well below applicable Radiation Protction Guides, often being near the statistical limit of detection

  14. Bone Marrow Regeneration Promoted by Biophysically Sorted Osteoprogenitors From Mesenchymal Stromal Cells

    Science.gov (United States)

    Poon, Zhiyong; Lee, Wong Cheng; Guan, Guofeng; Nyan, Lin Myint; Lim, Chwee Teck; Han, Jongyoon

    2015-01-01

    Human tissue repair deficiencies can be supplemented through strategies to isolate, expand in vitro, and reimplant regenerative cells that supplant damaged cells or stimulate endogenous repair mechanisms. Bone marrow-derived mesenchymal stromal cells (MSCs), a subset of which is described as mesenchymal stem cells, are leading candidates for cell-mediated bone repair and wound healing, with hundreds of ongoing clinical trials worldwide. An outstanding key challenge for successful clinical translation of MSCs is the capacity to produce large quantities of cells in vitro with uniform and relevant therapeutic properties. By leveraging biophysical traits of MSC subpopulations and label-free microfluidic cell sorting, we hypothesized and experimentally verified that MSCs of large diameter within expanded MSC cultures were osteoprogenitors that exhibited significantly greater efficacy over other MSC subpopulations in bone marrow repair. Systemic administration of osteoprogenitor MSCs significantly improved survival rates (>80%) as compared with other MSC subpopulations (0%) for preclinical murine bone marrow injury models. Osteoprogenitor MSCs also exerted potent therapeutic effects as “cell factories” that secreted high levels of regenerative factors such as interleukin-6 (IL-6), interleukin-8 (IL-8), vascular endothelial growth factor A, bone morphogenetic protein 2, epidermal growth factor, fibroblast growth factor 1, and angiopoietin-1; this resulted in increased cell proliferation, vessel formation, and reduced apoptosis in bone marrow. This MSC subpopulation mediated rescue of damaged marrow tissue via restoration of the hematopoiesis-supporting stroma, as well as subsequent hematopoiesis. Together, the capabilities described herein for label-freeisolation of regenerative osteoprogenitor MSCs can markedly improve the efficacy of MSC-based therapies. PMID:25411477

  15. A synthesized biophysical and social vulnerability assessment for Taiwan

    Science.gov (United States)

    Lee, Yung-Jaan

    2017-11-01

    Taiwan, located in the Western Pacific, is a country that is one of the most vulnerable to disasters that are associated with the changing climate; it is located within the Ring of Fire, which is the most geologically active region in the world. The environmental and geological conditions in Taiwan are sensitive and vulnerable to such disasters. Owing to increasing urbanization in Taiwan, floods and climate-related disasters have taken an increasing toll on human lives. As global warming accelerates the rising of sea levels and increasing of the frequency of extreme weather events, disasters will continue to affect socioeconomic development and human conditions. Under such circumstances, researchers and policymakers alike must recognize the importance of providing useful knowledge concerning vulnerability, disaster recovery and resilience. Strategies for reducing vulnerability and climate-related disaster risks and for increasing resilience involve preparedness, mitigation and adaptation. In the last two decades, extreme climate events have caused severe flash floods, debris flows, landslides, and other disasters and have had negative effects of many sectors, including agriculture, infrastructure and health. Since climate change is expected to have a continued impact on socio-economic development, this work develops a vulnerability assessment framework that integrates both biophysical and social vulnerability and supports synthesized vulnerability analyses to identify vulnerable areas in Taiwan. Owing to its geographical, geological and climatic features, Taiwan is susceptible to earthquakes, typhoons, droughts and various induced disasters. Therefore, Taiwan has the urgent task of establishing a framework for assessing vulnerability as a planning and policy tool that can be used to identify not only the regions that require special attention but also hotspots in which efforts should be made to reduce vulnerability and the risk of climate-related disaster. To

  16. Summary report of the consultants' meeting on nuclear data for production of therapeutic radioisotopes

    International Nuclear Information System (INIS)

    Haight, R.C.; Paviotti-Corcuera, R.

    2002-04-01

    This report summarizes the presentations, recommendations and conclusions of the Consultants' Meeting on Nuclear Data for Production of Therapeutic Radioisotopes. The purpose of this meeting was to discuss scientific and technical matters related to the subject and to advise the IAEA Nuclear Data Section (NDS) on the need and possible formation of a Coordinated Research Programme (CRP). Accurate and complete knowledge of nuclear data are essential for the production of radionuclides for therapy to achieve the specific activity and purity required for efficient and safe clinical application. The Consultants recommended updating and completing the data for production of radionuclides that are recognized to be important in therapy. In addition, the consultants recommend investigating other radionuclides that have a potential interest and for which there exists a medical rationale for therapeutic use. To date no serious effort has been devoted to evaluation of nuclear data for the reactor and accelerator production of therapeutic radionuclides. The IAEA is in the unique and privileged position to address this important public health related problem. Therefore, the consultants highly recommend the formation of a CRP with the title: 'Nuclear Data for Production of Therapeutic Radionuclides.' (author)

  17. Gastroesophageal reflux in children: radionuclide gastroesophagography

    International Nuclear Information System (INIS)

    Blumhagen, J.D.; Rudd, T.G.; Christie, D.L.

    1980-01-01

    Sixty-five symptomatic infants and children underwent radionuclide gastroesophagography, acid reflux testing, and barium esophagography with water-siphon testing to evaluate the clinical efficacy of the scintigraphic technique in detecting gastroesophageal reflux. After ingesting /sup 99m/Tc sulfur colloid in fruit juice, patients rested beneath the gamma camera for 30 to 60 min while esophageal activity was monitored continuously. By using the acid reflux test as a standard of comparison, the senstivity of radionuclide gastroesophagography was 75%. Because of its physiologic nature, low radiation exposure, and convenience, radionuclide gastroesophagography warrants further evaluation as a screening test for gastroesophageal reflux

  18. Determination of natural occurring radionuclides concentrations

    International Nuclear Information System (INIS)

    Stajic, J.; Markovic, V.; Krstic, D.; Nikezic, D.

    2011-01-01

    Tobacco smoke contains certain concentrations of naturally occurring radionuclides from radioactive chains of uranium and thorium - 214 Pb, 214 Bi, 228 Ac, 208 Tl, 226 Ra, 232 Th and 40 K. Inhaling of tobacco smoke leads to internal exposure of man. In order to estimate absorbed dose of irradiation it is necessary to determine concentrations of radionuclides present in the tobacco leaves. In this paper specific activities of naturally occurring radionuclides were measured in tobacco samples from cigarettes which are used in Serbia. [sr

  19. 2008 LANL radionuclide air emissions report

    Energy Technology Data Exchange (ETDEWEB)

    Fuehne, David P.

    2009-06-01

    The emissions of radionuclides from Department of Energy Facilities such as Los Alamos National Laboratory (LANL) are regulated by the Amendments to the Clean Air Act of 1990, National Emissions Standards for Hazardous Air Pollutants (40 CFR 61 Subpart H). These regulations established an annual dose limit of 10 mrem to the maximally exposed member of the public attributable to emissions of radionuclides. This document describes the emissions of radionuclides from LANL and the dose calculations resulting from these emissions for calendar year 2008. This report meets the reporting requirements established in the regulations.

  20. 2010 LANL radionuclide air emissions report /

    Energy Technology Data Exchange (ETDEWEB)

    Fuehne, David P.

    2011-06-01

    The emissions of radionuclides from Department of Energy Facilities such as Los Alamos National Laboratory (LANL) are regulated by the Amendments to the Clean Air Act of 1990, National Emissions Standards for Hazardous Air Pollutants (40 CFR 61 Subpart H). These regulations established an annual dose limit of 10 mrem to the maximally exposed member of the public attributable to emissions of radionuclides. This document describes the emissions of radionuclides from LANL and the dose calculations resulting from these emissions for calendar year 2010. This report meets the reporting requirements established in the regulations.

  1. Manual of bioassay procedures for radionuclides

    International Nuclear Information System (INIS)

    Pleskach, S.; Petkau, A.

    1986-06-01

    A monitoring program is described by which atomic radiation workers ar monitored for internal contamination with radionuclides in the workplace. The program involves analytical procedures for measuring alpha, beta and gamma activity in biological specimens, usually urine. Radionuclides are identified by their characteristic radiation using liquid scintillation counting, and alpha, beta and gamma spectrometry. Examples of calculating the minimum detectable activity for specific radionuclides are given and used to derive call-in-criteria in accordance with which the different groups of workers are monitored each month

  2. Solubility limited radionuclide transport through geologic media

    International Nuclear Information System (INIS)

    Muraoka, Susumu; Iwamoto, Fumio; Pigford, T.H.

    1980-11-01

    Prior analyses for the migration of radionuclides neglect solubility limits of resolved radionuclide in geologic media. But actually some of the actinides may appear in chemical forms of very low solubility. In the present report we have proposed the migration model with no decay parents in which concentration of radionuclide is limited in concentration of solubility in ground water. In addition, the analytical solutions of the space-time-dependent concentration are presented in the case of step release, band release and exponential release. (author)

  3. Soil - plant experimental radionuclide transfer factors

    International Nuclear Information System (INIS)

    Dobrin, R.I.; Dulama, C.N.; Toma, Al.

    2006-01-01

    Some experimental research was performed in our institute to assess site specific soil-plant transfer factors. A full characterization of an experimental site was done both from pedo-chemical and radiological point of view. Afterwards, a certain number of culture plants were grown on this site and the evolution of their radionuclide burden was then recorded. Using some soil amendments one performed a parallel experiment and the radionuclide root uptake was evaluated and recorded. Hence, transfer parameters were calculated and some conclusions were drawn concerning the influence of site specific conditions on the root uptake of radionuclides. (authors)

  4. DNA damage induced by radionuclide internal irradiation

    International Nuclear Information System (INIS)

    Cui Fengmei; Zhao Jingyong; Hong Chengjiao; Lao Qinhua; Wang Liuyi; Yang Shuqin

    2004-01-01

    Objective: To study the DNA damage of peripheral blood mononuclear cell (PBMC) in rats exposed to radionuclide internal irradiation. Methods: The radionuclides were injected into the rats and single cell get electrophoresis (SCGE) was performed to detect the length of DNA migration in the rat PBMC. Results: DNA migration in the rat PBMC increased with accumulative dose or dose-rate. It showed good relationship of dose vs. response and of dose-rate vs. response, both relationship could be described as linear models. Conclusion: Radionuclide internal irradiation could cause DNA damage in rat PBMC. (authors)

  5. Irrigation Requirement Estimation Using Vegetation Indices and Inverse Biophysical Modeling

    Science.gov (United States)

    Bounoua, Lahouari; Imhoff, Marc L.; Franks, Shannon

    2010-01-01

    We explore an inverse biophysical modeling process forced by satellite and climatological data to quantify irrigation requirements in semi-arid agricultural areas. We constrain the carbon and water cycles modeled under both equilibrium, balance between vegetation and climate, and non-equilibrium, water added through irrigation. We postulate that the degree to which irrigated dry lands vary from equilibrium climate conditions is related to the amount of irrigation. The amount of water required over and above precipitation is considered as an irrigation requirement. For July, results show that spray irrigation resulted in an additional amount of water of 1.3 mm per occurrence with a frequency of 24.6 hours. In contrast, the drip irrigation required only 0.6 mm every 45.6 hours or 46% of that simulated by the spray irrigation. The modeled estimates account for 87% of the total reported irrigation water use, when soil salinity is not important and 66% in saline lands.

  6. The case for biophysics super-groups in physics departments.

    Science.gov (United States)

    Hoogenboom, Bart W; Leake, Mark

    2018-06-04

    Increasing numbers of physicists engage in research activities that address biological questions from physics perspectives or strive to develop physics insights from active biological processes. The on-going development and success of such activities morph our ways of thinking about what it is to 'do biophysics' and add to our understanding of the physics of life. Many scientists in this research and teaching landscape are homed in physics departments. A challenge for a hosting department is how to group, name and structure such biophysicists to best add value to their emerging research and teaching but also to the portfolio of the whole department. Here we discuss these issues and speculate on strategies. Creative Commons Attribution license.

  7. Fragility of complexity biophysical systems by neutron scattering

    Energy Technology Data Exchange (ETDEWEB)

    Magazu, Salvatore [Dipartimento di Fisica, Universita di Messina, P.O. Box 55, I-98166 Messina (Italy)]. E-mail: smagazu@unime.it; Migliardo, Federica [Dipartimento di Fisica, Universita di Messina, P.O. Box 55, I-98166 Messina (Italy); Bellocco, Ersilia [Dipartimento di Chimica Organica e Biologica, Universita di Messina, I-98166 Messina (Italy); Lagana, Giuseppina [Dipartimento di Chimica Organica e Biologica, Universita di Messina, I-98166 Messina (Italy); Mondelli, Claudia [CNR-INFM OGG and CRS-SOFT, c/o ILL, 6 Jules Horowitz, BP 156, 38042 Grenoble Cedex 9 (France)

    2006-11-15

    Neutron scattering is an exceptional tool to investigate structural and dynamical properties of systems of biophysical interest, such as proteins, enzymes, lipids and sugars. Moreover, elastic neutron scattering enhances the investigation of atomic motions in hydrated proteins in a wide temperature range and on the picosecond timescale. Homologous disaccharides, such as trehalose, maltose and sucrose, are cryptobiotic substances, since they allow to many organisms to undergo in a 'suspended life' state, known as cryptobiosis in extreme environmental conditions. The present paper is aimed to discuss the fragility degree of disaccharides, as evaluated of the temperature dependence of the mean square displacement by elastic neutron scattering, in order to link this feature with their bioprotective functions.

  8. The physics, biophysics and technology of photodynamic therapy

    International Nuclear Information System (INIS)

    Wilson, Brian C; Patterson, Michael S

    2008-01-01

    Photodynamic therapy (PDT) uses light-activated drugs to treat diseases ranging from cancer to age-related macular degeneration and antibiotic-resistant infections. This paper reviews the current status of PDT with an emphasis on the contributions of physics, biophysics and technology, and the challenges remaining in the optimization and adoption of this treatment modality. A theme of the review is the complexity of PDT dosimetry due to the dynamic nature of the three essential components-light, photosensitizer and oxygen. Considerable progress has been made in understanding the problem and in developing instruments to measure all three, so that optimization of individual PDT treatments is becoming a feasible target. The final section of the review introduces some new frontiers of research including low dose rate (metronomic) PDT, two-photon PDT, activatable PDT molecular beacons and nanoparticle-based PDT. (topical review)

  9. EFFECTS OF ACOUSTIC STIMULATION ON BIOPHYSICAL PROFILE TESTING TIME

    Directory of Open Access Journals (Sweden)

    M. Pourissa

    2008-04-01

    Full Text Available Biophysical profile (BPP test is the most commonly used antenatal test of fetal well-being. Purpose of this study is determining the influence of acoustic stimulation (AS on BPP testing time. About 55 pregnant women at 35 to 42 weeks who referred to department of Obstetric & Gynecology at university of medical sciences, Tabriz, Iran, were selected randomly. We used abdominal ultrasound guidance to place buzzer like device with power of 110 dB at the skin surface of the maternal abdomen, close to the fetal head. BPP test performed and BPP mean testing time calculated before and after AS. Data compared and analyzed by paired t-test. The results showed that fetal AS reduces the overall mean testing time from 24 minutes to 5 minutes. This clinical application can be helpful in busy clinics when rapid assessment of fetal health is required.

  10. Biophysical information in asymmetric and symmetric diurnal bidirectional canopy reflectance

    Science.gov (United States)

    Vanderbilt, Vern C.; Caldwell, William F.; Pettigrew, Rita E.; Ustin, Susan L.; Martens, Scott N.; Rousseau, Robert A.; Berger, Kevin M.; Ganapol, B. D.; Kasischke, Eric S.; Clark, Jenny A.

    1991-01-01

    The authors present a theory for partitioning the information content in diurnal bidirectional reflectance measurements in order to detect differences potentially related to biophysical variables. The theory, which divides the canopy reflectance into asymmetric and symmetric functions of solar azimuth angle, attributes asymmetric variation to diurnal changes in the canopy biphysical properties. The symmetric function is attributed to the effects of sunlight interacting with a hypothetical average canopy which would display the average diurnal properties of the actual canopy. The authors analyzed radiometer data collected diurnally in the Thematic Mapper wavelength bands from two walnut canopies that received differing irrigation treatments. The reflectance of the canopies varied with sun and view angles and across seven bands in the visible, near-infrared, and middle infrared wavelength regions. Although one of the canopies was permanently water stressed and the other was stressed in mid-afternoon each day, no water stress signature was unambiguously evident in the reflectance data.

  11. The physics, biophysics and technology of photodynamic therapy.

    Science.gov (United States)

    Wilson, Brian C; Patterson, Michael S

    2008-05-07

    Photodynamic therapy (PDT) uses light-activated drugs to treat diseases ranging from cancer to age-related macular degeneration and antibiotic-resistant infections. This paper reviews the current status of PDT with an emphasis on the contributions of physics, biophysics and technology, and the challenges remaining in the optimization and adoption of this treatment modality. A theme of the review is the complexity of PDT dosimetry due to the dynamic nature of the three essential components -- light, photosensitizer and oxygen. Considerable progress has been made in understanding the problem and in developing instruments to measure all three, so that optimization of individual PDT treatments is becoming a feasible target. The final section of the review introduces some new frontiers of research including low dose rate (metronomic) PDT, two-photon PDT, activatable PDT molecular beacons and nanoparticle-based PDT.

  12. Biophysical constraints on the computational capacity of biochemical signaling networks

    Science.gov (United States)

    Wang, Ching-Hao; Mehta, Pankaj

    Biophysics fundamentally constrains the computations that cells can carry out. Here, we derive fundamental bounds on the computational capacity of biochemical signaling networks that utilize post-translational modifications (e.g. phosphorylation). To do so, we combine ideas from the statistical physics of disordered systems and the observation by Tony Pawson and others that the biochemistry underlying protein-protein interaction networks is combinatorial and modular. Our results indicate that the computational capacity of signaling networks is severely limited by the energetics of binding and the need to achieve specificity. We relate our results to one of the theoretical pillars of statistical learning theory, Cover's theorem, which places bounds on the computational capacity of perceptrons. PM and CHW were supported by a Simons Investigator in the Mathematical Modeling of Living Systems Grant, and NIH Grant No. 1R35GM119461 (both to PM).

  13. Biophysical characterisation of GlycoPEGylated recombinant human factor VIIa

    DEFF Research Database (Denmark)

    Plesner, Bitten; Westh, Peter; Nielsen, Anders D.

    2011-01-01

    The effects of GlycoPEGylation on the structural, kinetic and thermal stability of recombinant human FVIIa were investigated using rFVIIa and linear 10 kDa and branched 40 kDa GlycoPEGylated® recombinant human FVIIa derivatives. The secondary and tertiary structure of rFVIIa measured by circular...... dichroism (CD) was maintained upon PEGylation. In contrast, the thermal and kinetic stability of rFVIIa was affected by GlycoPEGylation, as the apparent unfolding temperature Tm measured by differential scanning calorimetry (DSC) and the temperature of aggregation, Tagg, measured by light scattering (LS......) both increased with GlycoPEGylation. Both Tm and Tagg were independent of the molecular weight and the shape of the PEG chain. From the present biophysical characterisation it is concluded that after GlycoPEGylation, rFVIIa appears to be unaffected structurally (secondary and tertiary structure...

  14. 19th International School of Biophysics "Ettore Majorana"

    CERN Document Server

    Blank, M; Bioelectrochemistry III : Charge Separation across Biomembranes

    1988-01-01

    This book contains aseries of review papers related to the lectures given at the Third Course on Bioelectrochemistry held at Erice in November 1988, in the framework of the International School of Biophysics. The topics covered by this course, "Charge Separation Across Biomembranes, " deal with the electrochemical aspects of some basic phenomena in biological systems, such as transport of ions, ATP synthesis, formation and maintenance of ionic and protonic gradients. In the first part of the course some preliminary lectures introduce the students to the most basic phenomena and technical aspects of membrane bioelectrochemistry. The remaining part of the course is devoted to the description of a selected group of membrane-enzyme systems, capable of promoting, or exploiting, the processes of separation of electrically charged entities (electrons or ions) across the membrane barrier. These systems are systematically discussed both from a structural and functional point of view. The effort of the many dis...

  15. The physics, biophysics and technology of photodynamic therapy

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, Brian C [Division of Biophysics and Bioimaging, Ontario Cancer Institute and Department of Medical Biophysics, University of Toronto, 610 University Avenue, Toronto, ON M5G 2M9 (Canada); Patterson, Michael S [Department of Medical Physics, Juravinski Cancer Centre and Department of Medical Physics and Applied Radiation Sciences, McMaster University, 699 Concession Street, Hamilton, ON L8V 5C2 (Canada)], E-mail: wilson@uhnres.utoronto.ca, E-mail: mike.patterson@jcc.hhsc.ca

    2008-05-07

    Photodynamic therapy (PDT) uses light-activated drugs to treat diseases ranging from cancer to age-related macular degeneration and antibiotic-resistant infections. This paper reviews the current status of PDT with an emphasis on the contributions of physics, biophysics and technology, and the challenges remaining in the optimization and adoption of this treatment modality. A theme of the review is the complexity of PDT dosimetry due to the dynamic nature of the three essential components-light, photosensitizer and oxygen. Considerable progress has been made in understanding the problem and in developing instruments to measure all three, so that optimization of individual PDT treatments is becoming a feasible target. The final section of the review introduces some new frontiers of research including low dose rate (metronomic) PDT, two-photon PDT, activatable PDT molecular beacons and nanoparticle-based PDT. (topical review)

  16. Apocynin: Chemical and Biophysical Properties of a NADPH Oxidase Inhibitor

    Directory of Open Access Journals (Sweden)

    Valdecir F. Ximenes

    2013-03-01

    Full Text Available Apocynin is the most employed inhibitor of NADPH oxidase (NOX, a multienzymatic complex capable of catalyzing the one-electron reduction of molecular oxygen to the superoxide anion. Despite controversies about its selectivity, apocynin has been used as one of the most promising drugs in experimental models of inflammatory and neurodegenerative diseases. Here, we aimed to study the chemical and biophysical properties of apocynin. The oxidation potential was determined by cyclic voltammetry (Epa = 0.76V, the hydrophobicity index was calculated (logP = 0.83 and the molar absorption coefficient was determined (e275nm = 1.1 × 104 M−1 cm−1. Apocynin was a weak free radical scavenger (as measured using the DPPH, peroxyl radical and nitric oxide assays when compared to protocatechuic acid, used here as a reference antioxidant. On the other hand, apocynin was more effective than protocatechuic acid as scavenger of the non-radical species hypochlorous acid. Apocynin reacted promptly with the non-radical reactive species H2O2 only in the presence of peroxidase. This finding is relevant, since it represents a new pathway for depleting H2O2 in cellular experimental models, besides the direct inhibition of NADPH oxidase. This could be relevant for its application as an inhibitor of NOX4, since this isoform produces H2O2 and not superoxide anion. The binding parameters calculated by fluorescence quenching showed that apocynin binds to human serum albumin (HSA with a binding affinity of 2.19 × 104 M−1. The association did not alter the secondary and tertiary structure of HSA, as verified by synchronous fluorescence and circular dichroism. The displacement of fluorescent probes suggested that apocynin binds to site I and site II of HSA. Considering the current biomedical applications of this phytochemical, the dissemination of these chemical and biophysical properties can be very helpful for scientists and physicians interested in the use of apocynin.

  17. Drought propagation and its relation with catchment biophysical characteristics

    Science.gov (United States)

    Alvarez-Garreton, C. D.; Lara, A.; Garreaud, R. D.

    2016-12-01

    Droughts propagate in the hydrological cycle from meteorological to soil moisture to hydrological droughts. To understand the drivers of this process is of paramount importance since the economic and societal impacts in water resources are directly related with hydrological droughts (and not with meteorological droughts, which have been most studied). This research analyses drought characteristics over a large region and identify its main exogenous (climate forcing) and endogenous (biophysical characteristics such as land cover type and topography) explanatory factors. The study region is Chile, which covers seven major climatic subtypes according to Köppen system, it has unique geographic characteristics, very sharp topography and a wide range of landscapes and vegetation conditions. Meteorological and hydrological droughts (deficit in precipitation and streamflow, respectively) are characterized by their durations and standardized deficit volumes using a variable threshold method, over 300 representative catchments (located between 27°S and 50°S). To quantify the propagation from meteorological to hydrological drought, we propose a novel drought attenuation index (DAI), calculated as the ratio between the meteorological drought severity slope and the hydrological drought severity slope. DAI varies from zero (catchment that attenuates completely a meteorological drought) to one (the meteorological drought is fully propagated through the hydrological cycle). This novel index provides key (and comparable) information about drought propagation over a wide range of different catchments, which has been highlighted as a major research gap. Similar drought indicators across the wide range of catchments are then linked with catchment biophysical characteristics. A thorough compilation of land cover information (including the percentage of native forests, grass land, urban and industrial areas, glaciers, water bodies and no vegetated areas), catchment physical

  18. Biophysics at the Boundaries: The Next Problem Sets

    Science.gov (United States)

    Skolnick, Malcolm

    2009-03-01

    The interface between physics and biology is one of the fastest growing subfields of physics. As knowledge of such topics as cellular processes and complex ecological systems advances, researchers have found that progress in understanding these and other systems requires application of more quantitative approaches. Today, there is a growing demand for quantitative and computational skills in biological research and the commercialization of that research. The fragmented teaching of science in our universities still leaves biology outside the quantitative and mathematical culture that is the foundation of physics. This is particularly inopportune at a time when the needs for quantitative thinking about biological systems are exploding. More physicists should be encouraged to become active in research and development in the growing application fields of biophysics including molecular genetics, biomedical imaging, tissue generation and regeneration, drug development, prosthetics, neural and brain function, kinetics of nonequilibrium open biological systems, metabolic networks, biological transport processes, large-scale biochemical networks and stochastic processes in biochemical systems to name a few. In addition to moving into basic research in these areas, there is increasing opportunity for physicists in industry beginning with entrepreneurial roles in taking research results out of the laboratory and in the industries who perfect and market the inventions and developments that physicists produce. In this talk we will identify and discuss emerging opportunities for physicists in biophysical and biotechnological pursuits ranging from basic research through development of applications and commercialization of results. This will include discussion of the roles of physicists in non-traditional areas apart from academia such as patent law, financial analysis and regulatory science and the problem sets assigned in education and training that will enable future

  19. Biophysical mechanisms of endotoxin neutralization by cationic amphiphilic peptides.

    Science.gov (United States)

    Kaconis, Yani; Kowalski, Ina; Howe, Jörg; Brauser, Annemarie; Richter, Walter; Razquin-Olazarán, Iosu; Iñigo-Pestaña, Melania; Garidel, Patrick; Rössle, Manfred; Martinez de Tejada, Guillermo; Gutsmann, Thomas; Brandenburg, Klaus

    2011-06-08

    Bacterial endotoxins (lipopolysaccharides (LPS)) are strong elicitors of the human immune system by interacting with serum and membrane proteins such as lipopolysaccharide-binding protein (LBP) and CD14 with high specificity. At LPS concentrations as low as 0.3 ng/ml, such interactions may lead to severe pathophysiological effects, including sepsis and septic shock. One approach to inhibit an uncontrolled inflammatory reaction is the use of appropriate polycationic and amphiphilic antimicrobial peptides, here called synthetic anti-LPS peptides (SALPs). We designed various SALP structures and investigated their ability to inhibit LPS-induced cytokine secretion in vitro, their protective effect in a mouse model of sepsis, and their cytotoxicity in physiological human cells. Using a variety of biophysical techniques, we investigated selected SALPs with considerable differences in their biological responses to characterize and understand the mechanism of LPS inactivation by SALPs. Our investigations show that neutralization of LPS by peptides is associated with a fluidization of the LPS acyl chains, a strong exothermic Coulomb interaction between the two compounds, and a drastic change of the LPS aggregate type from cubic into multilamellar, with an increase in the aggregate sizes, inhibiting the binding of LBP and other mammalian proteins to the endotoxin. At the same time, peptide binding to phospholipids of human origin (e.g., phosphatidylcholine) does not cause essential structural changes, such as changes in membrane fluidity and bilayer structure. The absence of cytotoxicity is explained by the high specificity of the interaction of the peptides with LPS. Copyright © 2011 Biophysical Society. Published by Elsevier Inc. All rights reserved.

  20. Biophysical and structural considerations for protein sequence evolution

    Directory of Open Access Journals (Sweden)

    Grahnen Johan A

    2011-12-01

    Full Text Available Abstract Background Protein sequence evolution is constrained by the biophysics of folding and function, causing interdependence between interacting sites in the sequence. However, current site-independent models of sequence evolutions do not take this into account. Recent attempts to integrate the influence of structure and biophysics into phylogenetic models via statistical/informational approaches have not resulted in expected improvements in model performance. This suggests that further innovations are needed for progress in this field. Results Here we develop a coarse-grained physics-based model of protein folding and binding function, and compare it to a popular informational model. We find that both models violate the assumption of the native sequence being close to a thermodynamic optimum, causing directional selection away from the native state. Sampling and simulation show that the physics-based model is more specific for fold-defining interactions that vary less among residue type. The informational model diffuses further in sequence space with fewer barriers and tends to provide less support for an invariant sites model, although amino acid substitutions are generally conservative. Both approaches produce sequences with natural features like dN/dS Conclusions Simple coarse-grained models of protein folding can describe some natural features of evolving proteins but are currently not accurate enough to use in evolutionary inference. This is partly due to improper packing of the hydrophobic core. We suggest possible improvements on the representation of structure, folding energy, and binding function, as regards both native and non-native conformations, and describe a large number of possible applications for such a model.

  1. Research progess on treatment of cancer with targeted radionuclide therapy

    International Nuclear Information System (INIS)

    Luo Jiawen; Zhang Caixia

    2008-01-01

    The new development and situation of targeted radionuclide therapy in oncology is described, which include radioimmunotherapy, peptide receptor radionuclide therapy, gene therapy and radionuclide labled chemotherapeutics therapy. The application research on labled carrier of those therapy is emphasized. Meanwhile, the research progess of indomethacin and its combined with targeted radionuclide therapy is also described. (authors)

  2. SR 97 - Radionuclide transport calculations

    Energy Technology Data Exchange (ETDEWEB)

    Lindgren, Maria [Kemakta Konsult AB, Stockholm (Sweden); Lindstroem, Fredrik [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden)

    1999-12-01

    An essential component of a safety assessment is to calculate radionuclide release and dose consequences for different scenarios and cases. The SKB tools for such a quantitative assessment are used to calculate the maximum releases and doses for the hypothetical repository sites Aberg, Beberg and Ceberg for the initial canister defect scenario and also for the glacial melting case for Aberg. The reasonable cases, i.e. all parameters take reasonable values, results in maximum biosphere doses of 5x10{sup -8} Sv/yr for Aberg, 3x10{sup -8} Sv/yr for Beberg and 1x10{sup -8} Sv/yr for Ceberg for peat area. These doses lie significantly below 0.15 mSv/yr. (A dose of 0.15 mSv/yr for unit probability corresponds to the risk limit of 10{sup -5} per year for the most exposed individuals recommended in regulations.) The conclusion that the maximum risk would lie well below 10{sup -5} per year is also demonstrated by results from the probabilistic calculations, which directly assess the resulting risk by combining dose and probability estimates. The analyses indicate that the risk is 2x10{sup -5} Sv/yr for Aberg, 8x10{sup -7} Sv/yr for Beberg and 3x10{sup -8} Sv/yr for Ceberg. The analysis shows that the most important parameters in the near field are the number of defective canisters and the instant release fraction. The influence from varying one parameter never changes the doses as much as an order of magnitude. In the far field the most important uncertainties affecting release and retention are associated with permeability and connectivity of the fractures in the rock. These properties affect several parameters. Highly permeable and well connected fractures imply high groundwater fluxes and short groundwater travel times. Sparsely connected or highly variable fracture properties implies low flow wetted surface along migration paths. It should, however, be remembered that the far-field parameters have little importance if the near-field parameters take their reasonable

  3. SR 97 - Radionuclide transport calculations

    International Nuclear Information System (INIS)

    Lindgren, Maria; Lindstroem, Fredrik

    1999-12-01

    An essential component of a safety assessment is to calculate radionuclide release and dose consequences for different scenarios and cases. The SKB tools for such a quantitative assessment are used to calculate the maximum releases and doses for the hypothetical repository sites Aberg, Beberg and Ceberg for the initial canister defect scenario and also for the glacial melting case for Aberg. The reasonable cases, i.e. all parameters take reasonable values, results in maximum biosphere doses of 5x10 -8 Sv/yr for Aberg, 3x10 -8 Sv/yr for Beberg and 1x10 -8 Sv/yr for Ceberg for peat area. These doses lie significantly below 0.15 mSv/yr. (A dose of 0.15 mSv/yr for unit probability corresponds to the risk limit of 10 -5 per year for the most exposed individuals recommended in regulations.) The conclusion that the maximum risk would lie well below 10 -5 per year is also demonstrated by results from the probabilistic calculations, which directly assess the resulting risk by combining dose and probability estimates. The analyses indicate that the risk is 2x10 -5 Sv/yr for Aberg, 8x10 -7 Sv/yr for Beberg and 3x10 -8 Sv/yr for Ceberg. The analysis shows that the most important parameters in the near field are the number of defective canisters and the instant release fraction. The influence from varying one parameter never changes the doses as much as an order of magnitude. In the far field the most important uncertainties affecting release and retention are associated with permeability and connectivity of the fractures in the rock. These properties affect several parameters. Highly permeable and well connected fractures imply high groundwater fluxes and short groundwater travel times. Sparsely connected or highly variable fracture properties implies low flow wetted surface along migration paths. It should, however, be remembered that the far-field parameters have little importance if the near-field parameters take their reasonable values. In that case almost all

  4. Radionuclide imaging of musculoskeletal infection

    Directory of Open Access Journals (Sweden)

    Christopher J. Palestro

    2007-09-01

    Full Text Available Radionuclide imaging studies are routinely used to evaluate patients suspected of having musculoskeletal infection. Three-phase bone imaging is readily available, relatively inexpensive, and very accurate in the setting of otherwise normal bone. Labeled leukocyte imaging should be used in cases of "complicating osteomyelitis" such as prosthetic joint infection. This test also is useful in clinically unsuspected diabetic pedal osteomyelitis as well as in the neuropathic joint. It is often necessary, however, to perform complementary bone marrow imaging, to maximize the accuracy of labeled leukocyte imaging. In contrast to other regions in the skeleton, labeled leukocyte imaging is not useful for diagnosing spinal osteomyelitis. At the moment, gallium is the preferred radionuclide procedure for this condition and is a useful adjunct to magnetic resonance imaging. FDG-PET likely will play an important role in the evaluation of musculoskeletal infection, especially spinal osteomyelitis, and may replace gallium imaging for this purpose.Estudos através de imagens com o uso de radionuclídeos são rotineiramente usadas para avaliar pacientes suspeitos de terem infecção músculo-esquelética. A imagem óssea em tridimensional é facilmente avaliável, relativamente de baixo custo, e muito precisa na localização de alterações ósseas. Imagem com leucócito marcado poderia ser usada nos casos de "osteomielite com complicações" tais como infecção prostética articular. Esse teste também é útil na não suspeita clinica de osteomielite associada ao pé diabético tanto quanto nas junções neuropáticas. É sempre necessário, por outro lado, realizar imagem complementar da medula óssea para aumentar a precisão da imagem com leucócito marcado. Em contraste com outras regiões no esqueleto, imagem com leucócito marcado não é útil para diagnosticar osteomielite da coluna vertebral. Até agora, o gálio é o radionuclídeo preferido para

  5. Enhancing the effect of radionuclide tumor targeting, using lysosomotropic weak bases

    International Nuclear Information System (INIS)

    Sundberg, Asa Liljegren; Steffen, Ann-Charlott

    2007-01-01

    Purpose: The aim of the present study was to investigate if treatment with lysosomotropic weak bases could increase the intracellular retention of radiohalogens and thereby increase the therapeutic effect of radionuclide tumor targeting. Methods and Materials: Four different lysosomotropic bases, chloroquine, ammonium chloride, amantadine, and thioridazine, were investigated for their ability to increase radiohalogen retention in vitro. The two most promising substances, chloroquine and ammonium chloride, were studied in several cell lines (A431, U343MGaCl2:6, SKOV-3, and SKBR-3) in combination with radiolabeled epidermal growth factor (EGF) or the HER2 binding affibody (Z HER2:4 ) 2 . Results: The uptake and retention of radionuclides was found to be substantially increased by simultaneous treatment with the lysosomotropic bases. The effect was, however, more pronounced in the epidermal growth factor:epidermal growth factor receptor (EGF:EGFR) system than in the (Z HER2:4 ) 2 :HER2 system. The therapeutic effect of ammonium chloride treatment combined with 211 At-EGF was also studied. The effect obtained after combined treatment was found to be much better than after 211 At-EGF treatment alone. Conclusions: The encouraging results from the present study indicate that the use of lysosomotropic weak bases is a promising approach for increasing the therapeutic effect of radionuclide targeting with radiohalogens

  6. Aligning physics and physiology: Engineering antibodies for radionuclide delivery.

    Science.gov (United States)

    Tsai, Wen-Ting K; Wu, Anna M

    2018-03-14

    The exquisite specificity of antibodies and antibody fragments renders them excellent agents for targeted delivery of radionuclides. Radiolabeled antibodies and fragments have been successfully used for molecular imaging and radioimmunotherapy (RIT) of cell surface targets in oncology and immunology. Protein engineering has been used for antibody humanization essential for clinical applications, as well as optimization of important characteristics including pharmacokinetics, biodistribution, and clearance. Although intact antibodies have high potential as imaging and therapeutic agents, challenges include long circulation time in blood, which leads to later imaging time points post-injection and higher blood absorbed dose that may be disadvantageous for RIT. Using engineered fragments may address these challenges, as size reduction and removal of Fc function decreases serum half-life. Radiolabeled fragments and pretargeting strategies can result in high contrast images within hours to days, and a reduction of RIT toxicity in normal tissues. Additionally, fragments can be engineered to direct hepatic or renal clearance, which may be chosen based on the application and disease setting. This review discusses aligning the physical properties of radionuclides (positron, gamma, beta, alpha, and Auger emitters) with antibodies and fragments and highlights recent advances of engineered antibodies and fragments in preclinical and clinical development for imaging and therapy. Copyright © 2018 John Wiley & Sons, Ltd.

  7. Determination of alpha radionuclides in fish

    International Nuclear Information System (INIS)

    Pernicka, L.; Matel, L.; Rosskopfova, O.

    2002-01-01

    The specific activity of alpha radionuclides was determined in biological samples. The biological samples were chosen in kinds of fish, concretely mackerels, herrings and haddocks. Experimental data were presented on the poster

  8. Phytoremediation of soils contaminated with radionuclides

    International Nuclear Information System (INIS)

    Yamaguchi, Isamu

    2004-01-01

    Aiming at efficient phytoremediation of soils contaminated with radionuclides, we examined the effect of soil microbes on the uptake ability of plants using the multitracer technique to find that tomato rhizofungi in Fusarium spp. can stimulate the uptake of 85 Sr and 137 Cs by the plants. The synergic effect of a nonpathogenic strain of F. oxysporum on the uptake of radionuclides by plants proved to be enhanced by introducing a phytochelatin synthase gene into the fungus. Since soil contamination by radionuclides is still an unsolved problem in many parts of the world. Studies on phytoremediation of polluted soil environment will be important for developing effective strategies and devising adequate techniques to reduce human risks caused by food contamination of radionuclides. (author)

  9. Radiation safety requirements for radionuclide laboratories

    International Nuclear Information System (INIS)

    2000-01-01

    The guide lays down the requirements for laboratories and storage rooms in which radioactive substances are used or stored as unsealed sources. In addition, some general instructions concerning work in radionuclide laboratories are set out

  10. Natural and anthropogenic radionuclides in the environment

    International Nuclear Information System (INIS)

    Hille, R.

    1984-01-01

    A survey is given on the actual knowledge about occurence and environmental relevancy of the most important radionuclides from natural and anthropogenic origin. The contribution of AGF installation is emphasized. (orig.) [de

  11. Application of radionuclides in nuclear technology

    International Nuclear Information System (INIS)

    Boeck, H.

    1983-07-01

    Four main applications of radionuclides in nuclear technology are presented which are level-, density- and thickness gauging and moisture determination. Each method is surveyed for its general principle, various designs, accuracy, errors and practical designs. (Author)

  12. Transfer of radionuclides into human milk

    International Nuclear Information System (INIS)

    Steiner, M.; Wirth, E.

    1998-01-01

    Up until now the potential radiation exposure to breast-fed babies due to contaminated human milk has not been taken into account, when deriving international limit values and reference levels for radionuclides in foodstuffs, in air at monitored work places or for exposures in the medical field. It was the aim of the research project 'Transfer of radionuclides into human milk' to quantify the transfer of incorporated radionuclides into mother's milk, and develop simple models to estimate the radiation exposure of babies through the ingestion of human milk. The study focused on considerations of the radiation exposure due to the ingestion of contaminated foodstuffs by the mother, the inhalation of radionuclides at monitored work places, and the administration of radiopharmaceuticals to breast-feeding mothers. The blocking of infant thyroid glands by stable iodine in the case of accidental releases of radioiodine was considered as well. (orig.) [de

  13. Radiation safety requirements for radionuclide laboratories

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    The guide lays down the requirements for laboratories and storage rooms in which radioactive substances are used or stored as unsealed sources. In addition, some general instructions concerning work in radionuclide laboratories are set out.

  14. Radionuclide transport in a single fissure

    International Nuclear Information System (INIS)

    Eriksen, T.E.

    1984-01-01

    Radionuclide migration has been studied in natural fissures running parallel to the axes of granitic drill cores. A short pulse of radionuclide solution was injected at one end of the fissure and the temporal change in radionuclide concentration of the eluate measured. At the end of each experiment the fissure was opened and the radionuclide distribution on the fissure surfaces measured. The retardation of 241 Am(III) at pH 8.2 as well as the variation in 235 Np(V) retardation with pH are found to be in good agreement with K d-values obtained in batch experiments. The reduction of (TcO - 4 ) to Tc(IV) leads as expected to increasing retardation.(author)

  15. Metabolic transformation of radionuclides in marine organisms

    International Nuclear Information System (INIS)

    Koyanagi, Taku

    1987-01-01

    Physico-chemical form of radionuclides is one of the important factors governing the concentration by marine organisms, whereas biological activities affect the existing states of radionuclides especially in coastal waters. Radioiodine in the form of iodate which is predominant species in seawater is reduced to iodide ion by biological activities and concentration factor of iodide is an order of magnitude higher than those of iodate. Extremely high accumulation of transition elements, actinides, or natural radionuclides in branchial heart of octopus is explained by the fuction of adenochrome, a glandular pigment in the organ as a natural complexing agent, and similar metal-binding proteins with relatively low molecular weight have been found in various marine invertebrates. High accumulation of some elements also found in mollusk kidney is considered to be caused by the intracellular concretions composed of calcium phosphate. All these biological processes suggest the significance of further investigations on metabolic transformation of radionuclides in marine organisms. (author)

  16. Relating β+ radionuclides' properties by order theory

    International Nuclear Information System (INIS)

    Quintero, N.Y.; Guillermo Restrepo; Cohen, I.M.; Universidad Tecnologica Nacional, Buenos Aires

    2013-01-01

    We studied 27 β + radionuclides taking into account some of their variants encoding information of their production, such as integral yield, threshold energy and energy of projectiles used to generate them; these radionuclides are of current use in clinical diagnostic imaging by positron emission tomography (PET). The study was conducted based on physical, physico-chemical, nuclear, dosimetric and quantum properties, which characterise the β + radionuclides selected, with the aim of finding meaningful relationships among them. In order to accomplish this objective the mathematical methodology known as formal concept analysis was employed. We obtained a set of logical assertions (rules) classified as implications and associations, for the set of β + radionuclides considered. Some of them show that low mass defect is related to high and medium values of maximum β + energy, and with even parity and low mean lives; all these parameters are associated to the dose received by a patient subjected to a PET analysis. (author)

  17. Behaviour of the radionuclides in the environment

    International Nuclear Information System (INIS)

    Lauria, Dejanira da Costa

    2007-01-01

    This chapter approaches the behaviour of radionuclides in the environment, the isotopes of the natural radioactive series, some aspects of the isotope behaviour on the environment and fission and activation radioactive isotopes

  18. Natural and Synthetic Barriers to Immobilize Radionuclides

    International Nuclear Information System (INIS)

    Um, W.

    2011-01-01

    The experiments of weathering of glass waste form and the reacted sediments with simulated glass leachates show that radionuclide sequestration can be significantly enhanced by promoting the formation of secondary precipitates. In addition, synthetic phosphate-bearing nanoporous material exhibits high stability at temperature and has a very high K d value for U(VI) removal. Both natural and synthetic barrier materials can be used as additional efficient adsorbents for retarding transport of radionuclides for various contaminated waste streams and waste forms present at U. S. Department of Energy clean-up sites and the proposed geologic radioactive waste disposal facility. In the radioactive waste repository facility, natural or synthetic materials are planned to be used as a barrier material to immobilize and retard radionuclide release. The getter material can be used to selectively scavenge the radionuclide of interest from a liquid waste stream and subsequently incorporate the loaded getters in a cementitious or various monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides from monolithic waste forms. Also, the getter material is to reduce the release of radionuclides form monolithic waste forms by being emplaced as a backfill barrier material around the wastes or waste form to minimize the potential around the wastes or waste form to minimize the potential hazard of leached radioactive wastes. The barrier material should be highly efficient to sequester radionuclides and possess physical and chemical stability for long-term exposure to severe weathering conditions. Because potential leaching of radionuclides depends on various environmental and weathering conditions of the near-field repository, the barrier materials must be durable and not disintegrate under a range of moisture, temperature, pressure, radiation, Eh, ph. and

  19. Radionuclides in plants in urban areas

    International Nuclear Information System (INIS)

    Todorovic, D.; Ajtic, J.; Popovic, D.; Nikolic, J.

    2009-01-01

    The results of a long-term study (from 2002 to 2008) on the concentrations of natural ( 7 Be, 210 Pb, 40 K) and fission ( 137 Cs) radionuclides in leaves of higher plants (linden and chestnut) in an urban area (city of Belgrade) are presented. The activity of the radionuclides was determined on an HPGe detector by standard gamma spectrometry. The study is a part of the ongoing air quality monitoring programme in urban areas in the Republic of Serbia. (author) [sr

  20. Limit of the radionuclides in granite

    International Nuclear Information System (INIS)

    Wang Shaling; Jiang Rangrong

    2003-01-01

    Granite is an important sort of building materials. Their radionuclide contents are limited by the national standard GB6566-2001 just as other building materials. This standard divides them into main materials and decorative materials, and relaxes the limit of the latter obviously. Owing to the consideration of public dose limit and environment protection, this method needs discussion. Otherwise, red granite contains high radionuclide contents relatively, especially the sort of Indian Red, and need be paid more attention

  1. Biogeochemistry of radionuclides in ecosystems (historical aspect)

    International Nuclear Information System (INIS)

    Ivanov, V.I.

    1991-01-01

    The paper presents the most important results of the study on the radionuclides' behaviour in natural and model biogeocenoses(ecosystems) obtained by N.W.Timofeev-Ressovskij and co-workers during the period 1947-1968. As early as at that period, radionuclides were classified according to the types of distribution, accumulation and migration within the surface and freshwater ecosystems, and the methods of biological purification of radioactive sewage were proposed

  2. Livermore Accelerator Source for Radionuclide Science (LASRS)

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Scott [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Bleuel, Darren [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Johnson, Micah [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Rusnak, Brian [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Soltz, Ron [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Tonchev, Anton [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-05-05

    The Livermore Accelerator Source for Radionuclide Science (LASRS) will generate intense photon and neutron beams to address important gaps in the study of radionuclide science that directly impact Stockpile Stewardship, Nuclear Forensics, and Nuclear Material Detection. The co-location of MeV-scale neutral and photon sources with radiochemical analytics provides a unique facility to meet current and future challenges in nuclear security and nuclear science.

  3. The uptake of radionuclides by plants

    International Nuclear Information System (INIS)

    Cawse, P.A.; Turner, G.S.

    1982-02-01

    A review of the literature, since 1970, on the research into the uptake of radionuclides by plants, with references to earlier soil and plant studies on the fate of nuclear weapons fallout. Experimental data on the uptake of plutonium isotopes, americium 241, cesium 137, radium 226, curium 244 and neptunium 237 and details of the chemical form of the radionuclide, soil type and plant growth period are tabulated. (U.K.)

  4. Transport of radionuclides from the LAMPF lagoons

    International Nuclear Information System (INIS)

    Ferenbaugh, R.W.; Purtymun, W.D.

    1985-01-01

    Monitoring of the discharge water from the Los Alamos Meson Physics Facility lagoons continued during June and December of 1983. The list of radionuclides being monitoring includes 7 Be, 57 Co, 134 Cs, 3 H, 54 Mn, 22 Na, and 83 Rb. The sampling locations and the data obtained to date are presented. Movement of radionuclides around the lagoons has been described in a previous report. 1 reference, 1 table

  5. Targeted radionuclide therapy for neuroendocrine tumours: principles and application.

    Science.gov (United States)

    Druce, Maralyn R; Lewington, Val; Grossman, Ashley B

    2010-01-01

    Neuroendocrine tumours comprise a group of neoplasms with variable clinical behaviour. Their growth and spread is often very slow and initially asymptomatic, and thus they are often metastatic at the time of diagnosis and incurable by surgery. An exciting therapeutic strategy for cytoreduction, both for stabilisation of tumour growth and inhibition of hormone production, is the use of targeted radionuclide therapy. Evidence from large-scale, randomised, placebo-controlled trials is very difficult to obtain in these rare diseases, but current data appear promising. It is timely to review the principles underlying the use of these therapies, together with the clinical outcomes to date and potential directions for future research. Copyright 2009 S. Karger AG, Basel.

  6. Radionuclides in forest biogeocenose elements

    International Nuclear Information System (INIS)

    Bulavik, I.M.; Zhuchenko, T.A.

    1992-01-01

    In 1991 year investigations are made on a studying of the radionuclide distribution (CS-137 and Sr-90) through the main forest biogeocenose elements (a litter a mineral soil layer, overground trees parts) on 5 experimental objects of Gomel' region with a various contamination. Radiation characters of the objects are done. As compared with 1989 year cesium and strontium migration from tress into the litter and from the litter to the soil is shown. In the litter and upper soil layer (5 m) contents of Cs-137 and Sr-90 are 95 and 80% accordingly. The Sr-90 concentration in the wood and the isotope concentration change through yearly layers (1986-1991 years) are studied. Wood layers formed to the accident have a lesser cesium concentration, especially in the oax-tree. The highest Cs and Se translocation, into the wood is noted in the pine the lesse one in the oax-tree. Among all elements of the biogeocenose the highest Cs-137 concentration the litter has and then one-year-old shoots, needles, lives, the bark and the wood go on. Even on the sixth year after the accident Cs concentration in the wood was 20-30 times less, than the one in needes and one-year-old shoot of this year. 4 refs.; 5 tabs

  7. Radionuclide transport in fractured media

    International Nuclear Information System (INIS)

    Williams, M.M.R.

    1993-01-01

    Until recently, the classical advective-dispersive transport equation was considered to be an adequate model for describing the motion of a solute (e.g. radionuclides) in porous and fractured media. In this model, the dispersion coefficient is either obtained from a microscopic model of the porous medium or by carefully controlled experiments. As a result of such experiments, a large body of data has been accumulated on the dispersivity. Detailed examination of these data has resulted in a curious phenomenon being discovered; namely, that the longitudinal dispersion length is 'scale-dependent'. That is to say the value deduced depends on the 'size' of the experiment, i.e. on the distance over which measurements are made. Several interesting attempts have been made to develop theories which explain this phenomenon, all based on treating the velocity of the water in the porous medium as a spatially random variable, but retaining the advective-dispersive balance equation. In this work we present an entirely new approach to the problem of solute transport in fractured media based upon an analogy with neutron transport. The new method has several advantages over the previous theories and these will be explained below. Results from the new theory are in agreement with experimental trends and do not require any further adjustment to explain the scale-dependent effect

  8. Monitoring radionuclides in marine organisms

    International Nuclear Information System (INIS)

    Ishii, T.; Matsuba, M.; Kurosawa, M.; Koyanagi, T.

    1990-01-01

    Concentration of stable elements corresponding to important radionuclides was determined by inductively coupled plasma atomic emission spectrometry (ICP-AES) and inductively coupled plasma mass spectrometry (ICP-MS) for various marine organisms to find indicator organisms for environmental monitoring. Both analytical techniques indicated linearity over a range of concentrations covering 2-4 orders of magnitude. Detection limits of elements by ICP-MS were 10 or 100 times higher than those of ICP-AES, although the precision and accuracy of ICP-MS was slightly inferior to that of ICP-AES. For quantitative analysis of elements with medium mass numbers (chromium, manganese, iron, nickel, copper, zinc, etc.), matrix interferences in ICP-MS were caused mainly by overlaps of spectra from coexisting elements in biological samples. The presence of background ions from atmosphere, water, and argon plasma interfered with determination of some isotopes. Most elements of high mass number could not be determined by ICP-AES because of its poor detection limits, whereas ICP-MS indicated high sensitivity and low background for elements of interest. We used ICP-MS analysis to determine the specific accumulation of certain elements in organs or tissues of 30 marine organisms

  9. Gut-related radionuclide studies

    International Nuclear Information System (INIS)

    Sullivan, M.F.

    1982-01-01

    This project is concerned with the behavior of radioactive materials that may be ingested as a consequence of a reactor accident, unavoidable occupational exposure, or after release to the environment and incorporation into the food chain. Current emphasis is directed toward evaluating hazards from ingested actinides as a function of animal age, species, nutrition, and diet, or chemicophysical state of the actinide. Recent observations indicate that the influence of chemical form on plutonium absorption observed at high mass levels does not occur at low mass concentrations. For example, at doses of 0.6 μg/kg there was no difference between absorption of the carbonate, citrate or nitrate forms of plutonium. However, at 1.5 mg/kg, the citrate was absorbed in quantities 30 times higher than the nitrate. The opposite effect occurred for neptunium GI absorption. Furthermore, it was demonstrated that materials such as citrus fruit juices and calcium, as well as drugs that affect GI function (such as aspirin and DTPA), markedly influence GI absorption of plutonium. Such studies provide evidence that diet and nutritional state should be considered in establishing safe limits for radionuclides that may be ingested

  10. Solubility limits on radionuclide dissolution

    Energy Technology Data Exchange (ETDEWEB)

    Kerrisk, J.F.

    1984-12-31

    This paper examines the effects of solubility in limiting dissolution rates of a number of important radionuclides from spent fuel and high-level waste. Two simple dissolution models were used for calculations that would be characteristics of a Yucca Mountain repository. A saturation-limited dissolution model, in which the water flowing through the repository is assumed to be saturated with each waste element, is very conservative in that it overestimates dissolution rates. A diffusion-limited dissolution model, in which element-dissolution rates are limited by diffusion of waste elements into water flowing past the waste, is more realistic, but it is subject to some uncertainty at this time. Dissolution rates of some elements (Pu, Am, Sn, Th, Zr, Sm) are always limited by solubility. Dissolution rates of other elements (Cs, Tc, Np, Sr, C, I) are never solubility limited; their release would be limited by dissolution of the bulk waste form. Still other elements (U, Cm, Ni, Ra) show solubility-limited dissolution under some conditions. 9 references, 3 tables.

  11. Radionuclides in an underground environment

    International Nuclear Information System (INIS)

    Thompson, J.L.

    1996-01-01

    In the 100 years since Becquerel recognized radioactivity, mankind has been very successful in producing large amounts of radioactive materials. We have been less successful in reaching a consensus on how to dispose of the billions of curies of fission products and transuranics resulting from nuclear weapons testing, electrical power generation, medical research, and a variety of other human endeavors. Many countries, including the United States, favor underground burial as a means of disposing of radioactive wastes. There are, however, serious questions about how such buried wastes may behave in the underground environment and particularly how they might eventually contaminate water, air and soil resources on which we are dependent. This paper describes research done in the United States in the state of Nevada on the behavior of radioactive materials placed underground. During the last thirty years, a series of ''experiments'' conducted for other purposes (testing of nuclear weapons) have resulted in a wide variety of fission products and actinides being injected in rock strata both above and below the water table. Variables which seem to control the movement of these radionuclides include the physical form (occlusion versus surface deposition), the chemical oxidation state, sorption by mineral phases of the host rock, and the hydrologic properties of the medium. The information gained from these studies should be relevant to planning for remediation of nuclear facilities elsewhere in the world and for long-term storage of nuclear wastes

  12. Radionuclides sorption in clay soils

    International Nuclear Information System (INIS)

    Siraky, G.; Lewis, C.; Hamlat, S.; Nollmann, C.E.

    1987-01-01

    The sorption behaviour of clay soils is examined through a parametric study of the distribution coefficient (Kd) for the radionuclides of interest, Cs and Sr. This work is a preliminary stage of the migration studies of these nuclides in a porous medium (ground of Ezeiza, Argentina) and the evaluation of radiologic impact of the removal of low and intermediate activity wastes in shallow trenches. The determination of Kd is performed by a static technique or batch. The phases are separated by centrifugation at 20000 g during 1 hour. The activity of supernatant solution of Cs-137 and Sr-85 is measured in a detecting system of I Na(Tl) well-type. Two types of parameters were changed: a) those related to the determination method: phase separation (centrifugation vs. centrifugation plus filtration); equilibrium period, ratio solid/liquid; b) those related to the geochemical system: pH of contact solution, carrier concentration, competitive ions, ionic strength, desorption. It was observed that the modification of parameters in the Kd-measurement does not change the order of magnitude of results. (Author)

  13. Migration of radionuclides through a river system

    Energy Technology Data Exchange (ETDEWEB)

    Matsunaga, Takeshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1999-03-01

    Migration behavior of several atmospherically-derived radionuclides in a river watershed was studied. A main interest was in their relocation from the ground soil of the watershed to a downstream region through a river. Studied radionuclides are: {sup 137}Cs generated by weapon tests in the atmosphere; {sup 210}Pb and {sup 7}Be of naturally occurring radionuclides; {sup 137}Cs, {sup 90}Sr, {sup 239,240}Pu and {sup 241}Am released by the Chernobyl nuclear power plant accident. Dominance of the form in suspended solid in river water (particulate form) was qualified for the radionuclides in the Kuji river watershed. An importance of discharge in flooding was also confirmed. A historical budget analysis for weapon test derived {sup 137}Cs was presented for the Hi-i river watershed and its accompanied lake sediment (Lake Shinji). The work afforded a scheme of a fate of {sup 137}Cs after falling on the ground soil and on the lake surface. Several controlling factors, which can influence on the chemical form of radionuclides discharged to a river, were also investigated in the vicinity of the Chernobyl nuclear power plant. A special attention was paid on the association of the radionuclides with dissolved species in water. Preferential association of Pu and Am isotopes to a large molecular size of dissolved matrices, probably of humic substances, was suggested. (author)

  14. Radionuclide Air Emissions Report for 2012

    Energy Technology Data Exchange (ETDEWEB)

    Wahl, Linnea [Ernest Orlando Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

    2013-05-01

    Berkeley Lab operates facilities where radionuclides are produced, handled, store d, and potentially emitted . These facilities are subject to the EPA radioactive air emission regulations in 40 CFR 61, Subpart H (EPA 1989a). Radionuclides may be emitted from stacks or vents on buildings where radionuclide production or use is authorized or they may be emitted as diffuse sources. In 2012, all Berkeley Lab sources were minor sources of radionuclides (sources resulting in a potential dose of less than 0.1 mrem/yr [0.001 mSv/yr]) . These minor sources include d about 140 stack sources and no diffuse sources . T here were no unplanned airborne radionuclide emissions from Berkeley Lab operations . Emissions from minor sources were measured by sampling or monitoring or were calculated based on quantities used, received for use, or produced during the year. Using measured and calculated emissions, and building- specific and common parameters, Laboratory personnel applied the EPA -approved computer code s, CAP88-PC and COMPLY , to calculate doses to the maximally exposed individual (MEI) at any offsite point where there is a residence, school, business, or office. Because radionuclides are used at three noncontiguous locations (the main site, Berkeley West Bio center, and Joint BioEnergy Institute), three different MEIs were identified.

  15. Inventories of selected radionuclides in the oceans

    International Nuclear Information System (INIS)

    1988-10-01

    In March 1984 an ad hoc Review Committee composed of senior experts in the marine radioactivity field made recommendations that ''the Monaco Laboratory should be engaged in compiling and evaluating the input of radionuclides into the marine environment''. The Committee recommended that work should commence on selected radionuclides, viz., 14 C, caesium isotopes, plutonium isotopes, 210 Po and 210 Pb followed by 226 Ra. Depending on the radionuclides involved the assistance of competent experts from outside as well as inside the IAEA was sought. The present document is a product of the work carried out within the framework of the above-mentioned task and contains reports on 14 C, 90 Sr, 137 Cs, 238 Pu, 239+240 Pu, 210 Pb, 210 Po and 226 Ra. Although the estimation of the inventory in the marine environment and related input and output fluxes, is the same for all radionuclides concerned, different approaches were followed to achieve this objective. These approaches depended on the geochemical characteristics of the radionuclides and the availability of data for different times and locations. For regions where data were lacking, extrapolation on the basis of specific assumptions has often been necessary. As the work was initiated during the pre-Chernobyl period, the radionuclides derived from the Chernobyl incident were not, in general, considered. Since the work for preparing the forthcoming report of the UNSCEAR is scheduled to be completed by 1991, it is hoped that the information contained in this volume will be beneficial. Refs, figs and tabs

  16. Using radionuclide imaging for monitoring repairment of bone defect with tissue-engineered bone graft in rabbits

    International Nuclear Information System (INIS)

    Xia Changsuo; Ye Fagang; Zou Yunwen; Ji Shixiang; Wang Dengchun

    2004-01-01

    Objective: To observe the effect of tissue-engineered bone grafts in repairing bone defect in rabbits, and assess the value of radionuclide for monitoring the therapeutic effect of this approach. Methods: Bilateral radial defects of 15 mm in length in 24 rabbits were made. The tissue-engineered bone grafts (composite graft) contained bone marrow stromal cells (BMSCs) of rabbits and calcium phosphate cement (CPC) were grafted in left side defects, CPC only grafts (artificial bone graft) in right defects. After the operation, radionuclide was used to monitor the therapeutic effects at 4, 8 and 12 weeks. Results: 99 Tc m -methylene diphosphonic acid (MDP) radionuclide bone imaging indicated that there was more radionuclide accumulation in grafting region of composite than that of CPC. There was significant difference between 99 Tc m -MDP uptake of the region of interest (ROI) and scintillant counts of composite bone and the artificial bone (P<0.01). Conclusion: Tissue-engineered bone grafts is eligible for repairing radial bone defects, and radionuclide imaging may accurately monitor the revascularization and bone regeneration after the bone graft implantation. (authors)

  17. E1B-attenuated onco lytic adenovirus enhances antitumor effect of radionuclide therapy by P53-independent way: cellular basic for radionuclide-viral therapy

    Energy Technology Data Exchange (ETDEWEB)

    Zhenwei, Zhang [Department of Nuclear Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Shanghai Institute of Biochemistry and Cell Biology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai (China); Hua, Wu; Xuemei, Zhang [Department of Nuclear Medicine, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan (China); Xinyuan, Liu [Shanghai Institute of Biochemistry and Cell Biology, Shanghai Institute for Biological Sciences, Chinese Academy of Sciences, Shanghai (China)

    2004-07-01

    Purpose: Chemotherapy or external radiation therapy can potentiate the therapeutic effect of E1 B-attenuated oncolytic adenovirus. In this study, the antitumor efficacy of oncolytic adenovirus combined with internal radionuclide therapy was evaluated. Methods: Firstly, viral replication was examined by plaque assay and Southern blotting, after oncolytic adenovirus, ZD55, was exposed to iodine-131. Cell viability was evaluated qualitatively by crystal violet staining and quantitatively by MTT assay. FACS analysis was performed to determine the synergic proapoptotic effect of iodine-131 combined with ZD55. Results: Irradiation of iodine-131 does not influence ZD55 viral DNA replication. In combination with ZD55, iodine-131 can efficiently kill tumor cells in a p53-independent model. ZD55 augments the proapoptotic effect of iodine-131. Conclusion: Radionuclide-viral therapy might be a novel tool for treatment of hepatocarcinoma. (authors)

  18. Production cross sections of short-lived silver radionuclides from natPd(p,xn) nuclear processes

    International Nuclear Information System (INIS)

    Khandaker, Mayeen Uddin; Kim, Kwangsoo; Kim, Guinyun

    2012-01-01

    Production cross-sections of short-lived 103 Ag, 104m Ag and 104g Ag radionuclides from proton-induced reactions on natural palladium (Pd) were measured up to 41 MeV by using a stacked-foil activation technique combined with high resolution γ-ray spectrometry. The present results are compared with the available literature values as well as theoretical data calculated by the TALYS and the ALICE-IPPE computer codes. Note that production cross-sections of the 104m Ag radionuclide from nat Pd(p,xn) processes has been measured here for the first time. Physical thick target yields for the investigated radionuclides were deduced from the respective threshold energy to 41 MeV taking into account that the total energy is absorbed in the targets. Measured data of the short-lived 103 Ag radionuclide are noteworthy due to its possible applications as a precursor for the indirect production of widely used therapeutic 103 Pd radionuclide via nat Pd(p,xn) 103 Ag → 103 Pd processes. On the other hand, the investigated 104 Ag radionuclide finds importance due to its potential use as a diagnostic and positron emission tomography (PET) imaging analogue. Above all, measured data will enrich the literature database leading to various applications in science and technology.

  19. Soil functional types: surveying the biophysical dimensions of soil security

    Science.gov (United States)

    Cécillon, Lauric; Barré, Pierre

    2015-04-01

    Soil is a natural capital that can deliver key ecosystem services (ES) to humans through the realization of a series of soil processes controlling ecosystem functioning. Soil is also a diverse and endangered natural resource. A huge pedodiversity has been described at all scales, which is strongly altered by global change. The multidimensional concept soil security, encompassing biophysical, economic, social, policy and legal frameworks of soils has recently been proposed, recognizing the role of soils in global environmental sustainability challenges. The biophysical dimensions of soil security focus on the functionality of a given soil that can be viewed as the combination of its capability and its condition [1]. Indeed, all soils are not equal in term of functionality. They show different processes, provide different ES to humans and respond specifically to global change. Knowledge of soil functionality in space and time is thus a crucial step towards the achievement soil security. All soil classification systems incorporate some functional information, but soil taxonomy alone cannot fully describe the functioning, limitations, resistance and resilience of soils. Droogers and Bouma [2] introduced functional variants (phenoforms) for each soil type (genoform) so as to fit more closely to soil functionality. However, different genoforms can have the same functionality. As stated by McBratney and colleagues [1], there is a great need of an agreed methodology for defining the reference state of soil functionality. Here, we propose soil functional types (SFT) as a relevant classification system for the biophysical dimensions of soil security. Following the definition of plant functional types widely used in ecology, we define a soil functional type as "a set of soil taxons or phenoforms sharing similar processes (e.g. soil respiration), similar effects on ecosystem functioning (e.g. primary productivity) and similar responses to global change (land-use, management or

  20. A saturable repair model for radionuclide therapy using low LET radiation emitters

    International Nuclear Information System (INIS)

    Calderon, Carlos F.; Joaquin Gonzalez; Guido Martin

    2004-01-01

    Purpose: In conventional radiotherapy doses of about 60Gy are necessary to achieve the tumor control or eradication. For systemic applications in radionuclide radiotherapy (RT) 0.1-0.5cGy/min and total dose 15-20 Gy could be reached with effective irradiation times of few days. The dose rate in tumor change exponentially as a time function where an uptake phase well differentiated from an elimination phase-will- appear both determined by the effective uptake and elimination times respectively. The biological response in RT will be determined not only by the total dose, but also by initial dose rate, the length of irradiation time (effective half-life) and biological factors, like radiosensitivity, repair and doubling times. Most quantitative models of radiation action on cells make the assumption that cell repair mechanisms are relevant in the response and it proceed in a dose-dependent way. The cell proliferation will influence too the response when the overall irradiation is comparable or greater than cell population doubling time. Many proposal had been made to apply radiobiological model for the prediction of the treatment response in RN. Saturable repair models are able, in principle, to explain the usual data base of radiobiological phenomena including which where other biophysical model does not work good. It is presented here an analytical expression to calculate the survival fraction in a cell population after irradiation based on a saturable repair radiobiological model proposed by Sanchez-Reyes [Sanchez-Reyes A. Radiact. Res., 1992;130:139-147] as function of radiobiological and biokinetics parameters which could be used in RN. The original radiobiological model consider a cell population where the DNA repair mechanisms are saturable and it could be affected by radiation action. The contribution of cell proliferation were considered keeping in mind that cell population grow up exponentially at constant rate. The dose rate was considered uniformly