Objective
CYTOGENETIC AND EPIDEMIOLOGICAL STUDIES SUGGEST THAT DNA REARRANGEMENTS ARE THE MAIN CAUSE FOR CANCER INDUCTION. EVIDENCE DERIVED FROM SEVERAL SOURCES IMPLICATES THE DNA DOUBLE STRAND BREAKS (DSB) IN DNA REARRANGEMENTS. INVESTIGATIONS WITH ULTRASOFT X-RAYS SHOW THAT THE RBE - VALUES FOR BOTH DSB AND CHROMOSOME ABERRATION INDUCTION INCREASE WITH DECREASING ELECTRON ENERGY. THE FOLLOWING INVESTIGATIONS WITH LOW ENERGY ELECTRONS ARE PROPOSED IN ORDER TO CONTRIBUTE TO RISK ASSESSMENTS AND IN SETTING UP EXPOSURE LIMITS.
Relative biological effectiveness (RBE) values, for cell transformations, of monoenergetic electrons in the range of several 100 eV to 10 keV have been determined.
Studies included:
determination of the transformation frequency in C3H10T1/2 cells using cobalt-60 gamma-rays as a reference radiation;
determination of the OER value for transformation of C3H10T1/2 cells;
evaluation of deoxyribonucleic acid (DNA) lesions involved in radiation induced cell transformation by comparing RBE and OER values for DNA lesions and cell transformation.
RBE - VALUES OF ELECTRONS OF DEFINITE ENERGIES WILL BE DETERMINED FOR CELL TRANSFORMATION. MONOENERGETIC ELECTRONS ARE PRODUCED WITHIN CELLS BY IRRADIATION WITH CHARACTERISTIC ULTRASOFT X-RAYS OF ENERGIES RANGING FROM SEVERAL HUNDRED EV UP TO ABOUT 10 KEV.
THESE X-RAYS ARE GENERATED BY BOMBARDING SUITABLE TARGETS WITH ACCELERATED PROTONS. THE USE OF PROTONS INSTEAD OF ELECTRONS PROVIDES AN ULTRASOFT X-RAY BEAM WITH NEGLIGIBLE BREMSSTRAHLUNG CONTAMINATION. THE INVESTIGATIONS WILL BE STARTED WITH CHROMIUM K CHARACTERISTIC X-RAYS (4.55 KEV) FOLLOWED BY ALUMINIUM K CHARACTERISTIC X-RAYS (1.5 KEV). THE RELATIVE BIOLOGICAL EFFECTIVENESS OF THESE CHARACTERISTIC X-RAYS (OR LOW ENERGY ELECTRONS) ARE RELATED TO THAT OF 60-CO GAMMA-RAYS.
BECAUSE OF THE DEFINED ENERGY AND SHORT RANGE OF THE PRODUCED ELECTRONS ULTRASOFT X-RAYS ARE AN EXCELLENT TOOL FOR PROBING THE SUBCELLULAR MECHANISMS OF RADIATION CARCINOGENESIS AND THE ROLE OF THE LOW ENERGETIC SECONDARY ELECTRONS WHICH ARE PRODUCED BY MOST RADIATIONS. CR K AND AL K CHARACTERISTIC X-RAYS OF PHOTON ENERGIES 4.55 AND 1.5 KEV RESPECTIVELY GENERATE SECONDARY ELECTRONS OF RANGES 600 NM AND 70 NM.
IT IS PLANNED TO USE C3H/10TI/2 MOUSE EMBRYO CELLS WHICH ARE ESTABLISHED FOR ONCOGENIC TRANSFORMATION STUDIES. IN DETAIL THE PROCEDURE IS AS FOLLOWS: FOR SURVIVAL STUDIES A SUFFICIENT NUMBER OF CELLS IS NEEDED PER DISH FOR EVALUATION OF THE COLONY FORMING ABILITY. FOR TRANSFORMATION SCORING ABOUT 300 VIABLE CELLS PER DISH ARE SEEDED. AFTER 6 WEEKS OF (CONFLUENT AND POST CONFLUENT) INCUBATION TRANSFORMED FOCI CAN BE IDENTIFIED. FROM THE TRANSFORMATION FREQUENCIES VERSUS ABSORBED DOSES THE RBE - VALUES CAN BE EVALUATED WHICH MAY BE DOSE DEPENDENT.
Fields of science (EuroSciVoc)
CORDIS classifies projects with EuroSciVoc, a multilingual taxonomy of fields of science, through a semi-automatic process based on NLP techniques. See: The European Science Vocabulary.
CORDIS classifies projects with EuroSciVoc, a multilingual taxonomy of fields of science, through a semi-automatic process based on NLP techniques. See: The European Science Vocabulary.
- natural sciences biological sciences genetics DNA
- natural sciences chemical sciences inorganic chemistry transition metals
- natural sciences chemical sciences inorganic chemistry post-transition metals
- natural sciences biological sciences genetics chromosomes
- natural sciences physical sciences theoretical physics particle physics photons
You need to log in or register to use this function
Programme(s)
Multi-annual funding programmes that define the EU’s priorities for research and innovation.
Multi-annual funding programmes that define the EU’s priorities for research and innovation.
Topic(s)
Calls for proposals are divided into topics. A topic defines a specific subject or area for which applicants can submit proposals. The description of a topic comprises its specific scope and the expected impact of the funded project.
Data not available
Calls for proposals are divided into topics. A topic defines a specific subject or area for which applicants can submit proposals. The description of a topic comprises its specific scope and the expected impact of the funded project.
Call for proposal
Procedure for inviting applicants to submit project proposals, with the aim of receiving EU funding.
Data not available
Procedure for inviting applicants to submit project proposals, with the aim of receiving EU funding.
Funding Scheme
Funding scheme (or “Type of Action”) inside a programme with common features. It specifies: the scope of what is funded; the reimbursement rate; specific evaluation criteria to qualify for funding; and the use of simplified forms of costs like lump sums.
Funding scheme (or “Type of Action”) inside a programme with common features. It specifies: the scope of what is funded; the reimbursement rate; specific evaluation criteria to qualify for funding; and the use of simplified forms of costs like lump sums.
Coordinator
85764 NEUHERBERG
Germany
The total costs incurred by this organisation to participate in the project, including direct and indirect costs. This amount is a subset of the overall project budget.