G. Terzoudi - Academia.edu (original) (raw)
Papers by G. Terzoudi
Radiation Research
Inter-laboratory exercises are important tools within the European network for biological dosimet... more Inter-laboratory exercises are important tools within the European network for biological dosimetry and physical retrospective dosimetry (RENEB) to validate and improve the performance of member laboratories and to ensure an operational network with high quality standards for dose estimations in case of a large-scale radiological or nuclear event. In addition to the RENEB inter-laboratory comparison 2021, several inter-laboratory comparisons have been performed in the frame of RENEB for a number of assays in recent years. This publication gives an overview of RENEB inter-laboratory comparisons for biological dosimetry assays in the past and a final summary of the challenges and lessons learnt from the RENEB inter-laboratory comparison 2021. In addition, the dose estimates of all RENEB inter-laboratory comparisons since 2013 that have been conducted for the dicentric chromosome assay, the most established and applied assay, are compared and discussed.
Radiation Research
After large-scale radiation accidents where many individuals are suspected to be exposed to ioniz... more After large-scale radiation accidents where many individuals are suspected to be exposed to ionizing radiation, biological and physical retrospective dosimetry assays are important tools to aid clinical decision making by categorizing individuals into unexposed/minimally, moderately or highly exposed groups. Quality-controlled inter-laboratory comparisons of simulated accident scenarios are regularly performed in the frame of the European legal association RENEB (Running the European Network of Biological and Physical retrospective Dosimetry) to optimize international networking and emergency readiness in case of large-scale radiation events. In total 33 laboratories from 22 countries around the world participated in the current RENEB inter-laboratory comparison 2021 for the dicentric chromosome assay. Blood was irradiated in vitro with X rays (240 kVp, 13 mA, ∼75 keV, 1 Gy/min) to simulate an acute, homogeneous whole-body exposure. Three blood samples (no. 1: 0 Gy, no. 2: 1.2 Gy, n...
International Journal of Radiation Biology, 2016
International Journal of Radiation Biology, 2016
International Journal of Radiation Biology, 2016
International Journal of Radiation Oncology*Biology*Physics, 2015
Microelectronic Engineering, 2002
Cytogenetic and Genome Research, 2004
Several studies have been carried out to evaluate the mutagenic and carcinogenic potential of atr... more Several studies have been carried out to evaluate the mutagenic and carcinogenic potential of atrazine, the most prevalent of triazine herbicides classified as a “possible human carcinogen”. The majority of these studies have been negative but positive responses have been also reported including mammary tumors in female Sprague-Dawley rats. Sister chromatid exchanges (SCEs) caused by the presence of DNA lesions at the moment of DNA replication have been extensively used for genotoxicity testing, but for non-cytotoxic exposures to atrazine controversial results have been reported. Even though exposures to higher concentrations of atrazine could provide clear evidence for its genotoxicity, conventional SCE analysis at metaphase cells cannot be used because affected cells are delayed in G2-phase and do not proceed to mitosis. As a result, the genotoxic potential of atrazine may have been underestimated. Since clear evidence has been recently reported relating SCEs to homologous recombi...
Biosensors and Bioelectronics, 2002
International Journal of Radiation Biology, 2016
![Research paper thumbnail of Lack of association between GSTT1 polymorphism and endogenous or benzo[a]pyrene-induced sister chromatid exchanges as analyzed in metaphase or G2-phase lymphocytes](https://attachments.academia-assets.com/94417616/thumbnails/1.jpg)
](Molecular Biology Reports, 2010
In Europe, a network for biological dosimetry has been created to strengthen the emergency prepar... more In Europe, a network for biological dosimetry has been created to strengthen the emergency preparedness and response cap-
Biological Dosimetry is a necessary support for national radiation protection programs and emerge... more Biological Dosimetry is a necessary support for national radiation protection programs and emergency response schemes. The Latin American Biological Dosimetry Network (LBDNet) has standing experience in biological dosiemtry network activities with several intercomparison exercises showing almost homogeneous results.. One way to increase the network response, overcoming the difficulties associated whit blood or slide transport is the scoring of dicentric on a computer monitor using electronically transmitted images i.e. the dicentric telescoring. This procedure remove the difficulties associated with the dispatching and reception of “physical” samples and is probably the most immediately way of share the scoring load among laboratories working in network. Here we present the results of two exercises organised by the LBDNet to test the efficiency of such an approach. During the first exercise, the participant laboratories analysed the same images derived from cells exposed at 0.5 Gy a...
Cytogenetic and Genome Research, 2004
Sister chromatid exchange (SCE) analysis in human peripheral blood lymphocytes is often applied a... more Sister chromatid exchange (SCE) analysis in human peripheral blood lymphocytes is often applied as a cytogenetic assay for biomonitoring and genotoxicity testing of potentially mutagenic and carcinogenic chemicals. Sister chromatid exchanges (SCEs) represent the interchange of DNA replication products at apparently homologous sites on the two chromatids of a single chromosome, and are indicative of DNA damage corrected by recombinational repair. Such a strand recombination (crossover) is believed to be the basis for the formation of SCEs. It has been found that S-phase dependent agents are very good inducers of SCEs, whereas ionizing radiation is a poor inducer (1). The evidence of SCE formation came from early studies (2) that demonstrated their occurrence during replication of chromosomes and paved the way to detect them easily. A breakthrough in the visualization of SCEs came in 1972-1974. It was then shown that, when a thymidine analogue such as 5-bromodeoxyuridine (BrdU) is inc...
HNPS Proceedings
The present study concerns the determination of the maximum acceptable contact dose rate per radi... more The present study concerns the determination of the maximum acceptable contact dose rate per radioac- tive waste package for safekeeping at the New Radioactive Waste Interim Storage (NRWIS) of the National Centre for Scientific Research “Demokritos” (NCSR “D”). The NRWIS facility is used for temporary storage of spent/ orphan sealed sources, devices like lightning rods and primary radioactive waste. The contact dose rate per package is determined in a level that even in case the highest radiation background is built up in- side the storage facility, the doses to the workers will not exceed the maximum permissible doses. The total dose that a worker receives inside the facility should not exceed one half of the annual occupational dose constraint of 6 mSv. Furthermore in cases of the highest radiation background inside the facility, shielding calculations are performed.
Radiation Research
Inter-laboratory exercises are important tools within the European network for biological dosimet... more Inter-laboratory exercises are important tools within the European network for biological dosimetry and physical retrospective dosimetry (RENEB) to validate and improve the performance of member laboratories and to ensure an operational network with high quality standards for dose estimations in case of a large-scale radiological or nuclear event. In addition to the RENEB inter-laboratory comparison 2021, several inter-laboratory comparisons have been performed in the frame of RENEB for a number of assays in recent years. This publication gives an overview of RENEB inter-laboratory comparisons for biological dosimetry assays in the past and a final summary of the challenges and lessons learnt from the RENEB inter-laboratory comparison 2021. In addition, the dose estimates of all RENEB inter-laboratory comparisons since 2013 that have been conducted for the dicentric chromosome assay, the most established and applied assay, are compared and discussed.
Radiation Research
After large-scale radiation accidents where many individuals are suspected to be exposed to ioniz... more After large-scale radiation accidents where many individuals are suspected to be exposed to ionizing radiation, biological and physical retrospective dosimetry assays are important tools to aid clinical decision making by categorizing individuals into unexposed/minimally, moderately or highly exposed groups. Quality-controlled inter-laboratory comparisons of simulated accident scenarios are regularly performed in the frame of the European legal association RENEB (Running the European Network of Biological and Physical retrospective Dosimetry) to optimize international networking and emergency readiness in case of large-scale radiation events. In total 33 laboratories from 22 countries around the world participated in the current RENEB inter-laboratory comparison 2021 for the dicentric chromosome assay. Blood was irradiated in vitro with X rays (240 kVp, 13 mA, ∼75 keV, 1 Gy/min) to simulate an acute, homogeneous whole-body exposure. Three blood samples (no. 1: 0 Gy, no. 2: 1.2 Gy, n...
International Journal of Radiation Biology, 2016
International Journal of Radiation Biology, 2016
International Journal of Radiation Biology, 2016
International Journal of Radiation Oncology*Biology*Physics, 2015
Microelectronic Engineering, 2002
Cytogenetic and Genome Research, 2004
Several studies have been carried out to evaluate the mutagenic and carcinogenic potential of atr... more Several studies have been carried out to evaluate the mutagenic and carcinogenic potential of atrazine, the most prevalent of triazine herbicides classified as a “possible human carcinogen”. The majority of these studies have been negative but positive responses have been also reported including mammary tumors in female Sprague-Dawley rats. Sister chromatid exchanges (SCEs) caused by the presence of DNA lesions at the moment of DNA replication have been extensively used for genotoxicity testing, but for non-cytotoxic exposures to atrazine controversial results have been reported. Even though exposures to higher concentrations of atrazine could provide clear evidence for its genotoxicity, conventional SCE analysis at metaphase cells cannot be used because affected cells are delayed in G2-phase and do not proceed to mitosis. As a result, the genotoxic potential of atrazine may have been underestimated. Since clear evidence has been recently reported relating SCEs to homologous recombi...
Biosensors and Bioelectronics, 2002
International Journal of Radiation Biology, 2016
Molecular Biology Reports, 2010
In Europe, a network for biological dosimetry has been created to strengthen the emergency prepar... more In Europe, a network for biological dosimetry has been created to strengthen the emergency preparedness and response cap-
Biological Dosimetry is a necessary support for national radiation protection programs and emerge... more Biological Dosimetry is a necessary support for national radiation protection programs and emergency response schemes. The Latin American Biological Dosimetry Network (LBDNet) has standing experience in biological dosiemtry network activities with several intercomparison exercises showing almost homogeneous results.. One way to increase the network response, overcoming the difficulties associated whit blood or slide transport is the scoring of dicentric on a computer monitor using electronically transmitted images i.e. the dicentric telescoring. This procedure remove the difficulties associated with the dispatching and reception of “physical” samples and is probably the most immediately way of share the scoring load among laboratories working in network. Here we present the results of two exercises organised by the LBDNet to test the efficiency of such an approach. During the first exercise, the participant laboratories analysed the same images derived from cells exposed at 0.5 Gy a...
Cytogenetic and Genome Research, 2004
Sister chromatid exchange (SCE) analysis in human peripheral blood lymphocytes is often applied a... more Sister chromatid exchange (SCE) analysis in human peripheral blood lymphocytes is often applied as a cytogenetic assay for biomonitoring and genotoxicity testing of potentially mutagenic and carcinogenic chemicals. Sister chromatid exchanges (SCEs) represent the interchange of DNA replication products at apparently homologous sites on the two chromatids of a single chromosome, and are indicative of DNA damage corrected by recombinational repair. Such a strand recombination (crossover) is believed to be the basis for the formation of SCEs. It has been found that S-phase dependent agents are very good inducers of SCEs, whereas ionizing radiation is a poor inducer (1). The evidence of SCE formation came from early studies (2) that demonstrated their occurrence during replication of chromosomes and paved the way to detect them easily. A breakthrough in the visualization of SCEs came in 1972-1974. It was then shown that, when a thymidine analogue such as 5-bromodeoxyuridine (BrdU) is inc...
HNPS Proceedings
The present study concerns the determination of the maximum acceptable contact dose rate per radi... more The present study concerns the determination of the maximum acceptable contact dose rate per radioac- tive waste package for safekeeping at the New Radioactive Waste Interim Storage (NRWIS) of the National Centre for Scientific Research “Demokritos” (NCSR “D”). The NRWIS facility is used for temporary storage of spent/ orphan sealed sources, devices like lightning rods and primary radioactive waste. The contact dose rate per package is determined in a level that even in case the highest radiation background is built up in- side the storage facility, the doses to the workers will not exceed the maximum permissible doses. The total dose that a worker receives inside the facility should not exceed one half of the annual occupational dose constraint of 6 mSv. Furthermore in cases of the highest radiation background inside the facility, shielding calculations are performed.