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Biological dosimetry enables individual dose reconstruction in the case of unclear or inconsistent radiation exposure situations, especially when a direct measurement of ionizing radiation is not or is no longer possible. To be prepared for large-scale radiological incidents, networking between well-trained laboratories has been identified as a useful approach for provision of the fast and trustworthy dose assessments needed in such circumstances. To this end, various biodosimetry laboratories worldwide have joined forces and set up regional and/or nationwide networks either on a formal or informal basis. Many of these laboratories are also a part of global networks such as those organized by World Health Organization, International Atomic Energy Agency or Global Health Security Initiative. In the present report, biodosimetry networks from different parts of the world are presented, and the partners, activities and cooperation actions are detailed. Moreover, guidance for situational application of tools used for individual dosimetry is given.

High levels of scatter radiation in catheterization laboratories may lead to posterior subcapsular opacities in the lens of the staff. The international Retrospective Evaluation of Lens Injuries and Dose (RELID) was performed in Argentina for the first time in 2010 in the context of the congress of the Latin American Society of Interventional Cardiology (SOLACI) and recently, in 2014, was carried out for the second time (SOLACI-CACI 2014). The 2014 study included 115 participants: interventional cardiologists, technicians and nurses. Posterior subcapsular lens changes typical of ionizing radiation exposure were found in 91.5% of interventional cardiologists, in 77% of technicians and in 100% of nurses, according to the Merriam-Focht scale. This RELID study (Argentina 2014) has particular importance since it allowed the follow-up of 10 professionals evaluated in 2010. The results obtained in the study population highlight the importance of the availability and proper use of the elements of radiation protection, as well as staff training., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The BioDoseNet was founded by the World Health Organization as a global network of biodosimetry laboratories for building biodosimetry laboratory capacities in countries. The newly established BioDoseNet image repository is a databank of ~25 000 electronically captured images of metaphases from the dicentric assay, which have been previously analysed by international experts. The detailed scoring results and dose estimations have, in most cases, already been published. The compilation of these images into one image repository provides a valuable tool for training and research purposes in biological dosimetry. No special software is needed to view and score the image galleries. For those new to the dicentric assay, the BioDoseNet Image Repository provides an introduction to and training for the dicentric assay. It is an excellent instrument for intra-laboratory training purposes or inter-comparisons between laboratories, as recommended by the International Organization for Standardisation standards. In the event of a radiation accident, the repository can also increase the surge capacity and reduce the turnaround time for dose estimations. Finally, it provides a mechanism for the discussion of scoring discrepancies in difficult cases., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Mitotic Index (MI) estimation expressed as percentage of mitosis plays an important role as quality control endpoint. To this end, MI is applied to check the lot of media and reagents to be used throughout the assay and also to check cellular viability after blood sample shipping, indicating satisfactory/unsatisfactory conditions for the progression of cell culture. The objective of this paper was to apply the CellProfiler open-source software for automatic detection of mitotic and nuclei figures from digitized images of cultured human lymphocytes for MI assessment, and to compare its performance to that performed through semi-automatic and visual detection. Lymphocytes were irradiated and cultured for mitosis detection. Sets of images from cultures were analyzed visually and findings were compared with those using CellProfiler software. The CellProfiler pipeline includes the detection of nuclei and mitosis with 80% sensitivity and more than 99% specificity. We conclude that CellProfiler is a reliable tool for counting mitosis and nuclei from cytogenetic images, saves considerable time compared to manual operation and reduces the variability derived from the scoring criteria of different scorers. The CellProfiler automated pipeline achieves good agreement with visual counting workflow, i.e. it allows fully automated mitotic and nuclei scoring in cytogenetic images yielding reliable information with minimal user intervention., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Acute and late radiation-induced injury on skin and subcutaneous tissues are associated with substantial morbidity in radiation therapy, interventional procedures and also are of concern in the context of nuclear or radiological accidents. Pathogenesis is initiated by depletion of acutely responding epithelial tissues and damage to vascular endothelial microvessels. Efforts for medical management of severe radiation-induced lesions have been made. Nevertheless, the development of strategies to promote wound healing, including stem cell therapy, is required. From 1997 to 2014, over 248 patients were referred to the Radiopathology Committee of Hospital de Quemados del Gobierno de la Ciudad de Buenos Aires (Burns Hospital) for the diagnosis and therapy of radiation-induced localized lesions. As part of the strategies for the management of severe cases, there is an ongoing research and development protocol on 'Translational Clinical Trial phases I/II to evaluate the safety and efficacy of adult mesenchymal stem cells from bone marrow for the treatment of large burns and radiological lesions'. The object of this work was to describe the actions carried out by the Radiopathology Committee of the Burns Hospital in a chronic case with more than 30 years of evolution without positive response to conventional treatments. The approach involved the evaluation of the tissular compromise of the lesion, the prognosis and the personalized treatment, including regenerative therapy., (© World Health Organisation 2016. All rights reserved. The World Health Organization has granted Oxford University Press permission for the reproduction of this article.)

Biological Dosimetry is a necessary support for national radiation protection programmes and emergency response schemes. The Latin American Biological Dosimetry Network (LBDNet) was formally founded in 2007 to provide early biological dosimetry assistance in case of radiation emergencies in the Latin American Region. Here are presented the main topics considered in the foundational document of the network, which comprise: mission, partners, concept of operation, including the mechanism to request support for biological dosimetry assistance in the region, and the network capabilities. The process for network activation and the role of the coordinating laboratory during biological dosimetry emergency response is also presented. This information is preceded by historical remarks on biological dosimetry cooperation in Latin America. A summary of the main experimental and practical results already obtained by the LBDNet is also included., (© The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

It has been observed that victims of accidental overexposures show better chance of survival if they receive medical treatment early. The increased risk of scenarios involving mass casualties has stimulated the scientific community to develop tools that would help the medical doctors to treat victims. The biological dosimetry has become a routine test to estimate the dose, supplementing physical and clinical dosimetry. In case of radiation emergencies, in order to provide timely and effectively biological dosimetry assistance it is essential to guarantee an adequate transport of blood samples in principal, for providing support to countries that do not have biodosimetry laboratories. The objective of the present paper is to provide general guidelines, summarised in 10 points, for timely and proper receiving and sending of blood samples under National and International regulations, for safe and expeditious international transport. These guidelines cover the classification, packaging, marking, labelling, refrigeration and documentation requirements for the international shipping of blood samples and pellets, to provide assistance missions with a tool that would contribute with the preparedness for an effective biodosimetric response in cases of radiological or nuclear emergencies., (© The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

The bottleneck in data acquisition during biological dosimetry based on a dicentric assay is the need to score dicentrics in a large number of lymphocytes. One way to increase the capacity of a given laboratory is to use the ability of skilled operators from other laboratories. This can be done using image analysis systems and distributing images all around the world. Two exercises were conducted to test the efficiency of such an approach involving 10 laboratories. During the first exercise (E1), the participant laboratories analysed the same images derived from cells exposed to 0.5 and 3 Gy; 100 images were sent to all participants for both doses. Whatever the dose, only about half of the cells were complete with well-spread metaphases suitable for analysis. A coefficient of variation (CV) on the standard deviation of ∼15 % was obtained for both doses. The trueness was better for 3 Gy (0.6 %) than for 0.5 Gy (37.8 %). The number of estimated doses classified as satisfactory according to the z-score was 3 at 0.5 Gy and 8 at 3 Gy for 10 dose estimations. In the second exercise, an emergency situation was tested, each laboratory was required to score a different set of 50 images in 2 d extracted from 500 downloaded images derived from cells exposed to 0.5 Gy. Then the remaining 450 images had to be scored within a week. Using 50 different images, the CV on the estimated doses (79.2 %) was not as good as in E1, probably associated to a lower number of cells analysed (50 vs. 100) or from the fact that laboratories analysed a different set of images. The trueness for the dose was better after scoring 500 cells (22.5 %) than after 50 cells (26.8 %). For the 10 dose estimations, the number of doses classified as satisfactory according to the z-score was 9, for both 50 and 500 cells. Overall, the results obtained support the feasibility of networking using electronically transmitted images. However, before its implementation some issues should be elucidated, such as the number and resolution of the images to be sent, and the harmonisation of the scoring criteria. Additionally, a global website able to be used for the different regional networks, like Share Points, will be desirable to facilitate worldwide communication.

Human blood was irradiated with accelerated ions: 20 MeV 4He, 425 MeV 12C and 1480 MeV and 996 MeV 16O. For each ion, the blood was exposed to a range of doses as thin specimens in the track segment mode, so that irradiations took place at nearly constant LETs of 31.4, 61, 52 and 69 keV microm(-1), respectively. Lymphocytes were cultured to the first in vitro metaphase, analysed for chromosomal damage and the dicentric aberration frequencies fitted to the linear quadratic model of dose-response. For these high LET radiations, the linear (alpha) yield coefficient predominated and increased with LET, at least up to 60 keV microm(-1). Apart from the 996 MeV oxygen ions, the data indicated the presence of a quadratic (beta) coefficient, statistically consistent with values obtained with low LET radiations. However, the associated uncertainties on the measured beta values were large, illustrating the general problem that beta is more difficult to measure against a dominating and ever-increasing alpha term. The existence or otherwise of a beta component of the dose-response at these radiation qualities has important consequences for modelling mechanisms of aberration induction by radiation.