scholarly journals Radiosensitivity and transgenerational effects in non-human species

2018 ◽  
Vol 47 (3-4) ◽  
pp. 327-341 ◽  
Author(s):  
C. Adam-Guillermin ◽  
T. Hertal-Aas ◽  
D. Oughton ◽  
L. Blanchard ◽  
F. Alonzo ◽  
...  
Keyword(s):  
Radiation Protection ◽  
Radiation Sensitivity ◽  
Ionising Radiation ◽  
Transgenerational Effects ◽  
Dna Mutation ◽  
Relative Contribution ◽  
Effects Of Radiation ◽  
Hereditary Effects

The ALLIANCE working group on effects of ionising radiation on wildlife brings together European researchers to work on the topics of radiosensitivity and transgenerational effects in non-human biota. Differences in radiation sensitivity across species and phyla are poorly understood, but have important implications for understanding the overall effects of radiation and for radiation protection; for example, sensitive species may require special attention in monitoring and radiation protection, and differences in sensitivity between species also lead to overall effects at higher levels (community, ecosystem), since interactions between species can be altered. Hence, understanding the mechanisms of interspecies radiation sensitivity differences may help to clarify mechanisms underpinning intraspecies variation. Differences in sensitivity may only be revealed when organisms are exposed to ionising radiation over several generations. This issue of potential long-term or hereditary effects for both humans and wildlife exposed to low doses of ionising radiation is a major concern. Animal and plant studies suggest that gamma irradiation can lead to observable effects in the F1 generation that are not attributable to inheritance of a rare stable DNA mutation. Several studies have provided evidence of an increase in genomic instability detected in germ or somatic cells of F1 organisms from exposed F0 organisms. This can lead to induced radiosensitivity, and can result in phenotypic effects or lead to reproductive effects and teratogenesis. In particular, studies have been conducted to understand the possible role of epigenetic modifications, such as DNA methylation, histone modifications, or expression of non-coding RNAs in radiosensitivity, as well as in adaptation effects. As such, research using biological models in which the relative contribution of genetic and epigenetic processes can be elucidated is highly valuable.

scholarly journals Etiology of differentiated carcinoma of the thyroid current apprehension

2003 ◽  
Vol 50 (3) ◽  
pp. 51-55
Author(s):  
Ruben Han
Keyword(s):  
Animal Experiments ◽  
Growth Control ◽  
Significant Risk ◽  
Ionising Radiation ◽  
Sodium Iodide Symporter ◽  
Chemical Agents ◽  
Tsh Secretion ◽  
Genetic And Environmental Factors

It is apparent that in the last decade carcinoma of the thyroid is becoming increasingly prevalent. The multistage complex theory of thyroid carcinogenesis is based on observations made on cohort patients studies and during animal experiments over a period of last fifty years. The process of thyroid oncogenesis is conceived to be a series of events induced by genetic and environmental factors which alter follicular cells division and growth control. These factors can be considered as initiators (chemical agents and ionising radiation) and promoters (some goitrogenes and drugs). The first class of factors induce incipient tumorigenesis while the second augments TSH secretion and radically increases tumour growth. Normally silent, intracellular proto-oncogenes (of which Ret/PTC series are the most conceived ones) can become activated by chromosomal translocations, deletions or mutations and can transform normal follicular cell into a condition of uncontrolled division and growth. The most significant known cause of thyroid carcinomas in men is exposure to external or internal ionising radiation. Beside that, long-term iodine deficiency, effects of certain chemical carcinogens, drugs and goitrogenes must be considered as significant risk factors. Possible role of sodium/iodide symporter is becoming an objective of the most recent investigations.

scholarly journals An extreme sea level indicator for the contiguous United States coastline

2019 ◽  
Vol 6 (1) ◽  
Author(s):  
Md. Mamunur Rashid ◽  
Thomas Wahl ◽  
Don P. Chambers ◽  
Francisco M. Calafat ◽  
William V. Sweet
Keyword(s):  
United States ◽  
Sea Level ◽  
Decadal Variability ◽  
Level Indicator ◽  
Relative Contribution ◽  
Level Data ◽  
Water Level Data ◽  
The Individual

AbstractWe develop an aggregated extreme sea level (ESL) indicator for the contiguous United States coastline, which is comprised of separate indicators for mean sea level (MSL) and storm surge climatology (SSC). We use water level data from tide gauges to estimate interannual to multi-decadal variability of MSL and SSC and identify coastline stretches where the observed changes are coherent. Both the MSL and SSC indicators show significant fluctuations. Indicators of the individual components are combined with multi-year tidal contributions into aggregated ESL indicators. The relative contribution of the different components varies considerably in time and space. Our results highlight the important role of interannual to multi-decadal variability in different sea level components in exacerbating, or reducing, the impacts of long-term MSL rise over time scales relevant for coastal planning and management. Regularly updating the proposed indicator will allow tracking changes in ESL posing a threat to many coastal communities, including the identification of periods where the likelihood of flooding is particularly large or small.

Experience in implementing ICRP recommendations: IRPA's perspective on the role of the radiation protection professional

2012 ◽  
Vol 41 (3-4) ◽  
pp. 305-312
Author(s):  
K.R. Kase
Keyword(s):  
Radiation Protection ◽  
Ionising Radiation ◽  
International Congress ◽  
International Commission ◽  
Radiological Protection ◽  
International Organisations ◽  
The Future ◽  
International Body

The International Radiation Protection Association (IRPA) has a membership of approximately 17,000 individuals who are members of 48 national societies in 60 countries worldwide. As such, IRPA's vision is to be recognised as the international voice of the radiation protection professional. This article will discuss elements of the outcome of the 12th International Congress of IRPA (‘Focus on the future’), objectives and current activities of IRPA, criteria and priorities for the engagement of IRPA with international organisations, current IRPA initiatives in the areas of radiation protection culture and certification/qualification of radiation protection experts, planning for the 13th International Congress of IRPA, comments on the implementation of recent recommendations of the International Commission on Radiological Protection (ICRP), and suggestions about IRPA and ICRP collaboration in their implementation. IRPA recognises that ICRP is the international body to determine policy and to make recommendations for protection against ionising radiation, and IRPA is in a position to participate in and facilitate the implementation of those recommendations.

Radiation Safety

2018 ◽  
Author(s):  
Erin M. Maddy ◽  
Kevin Abnet ◽  
Geoffrey Scriver ◽  
Mrinal Shukla
Keyword(s):  
Best Practices ◽  
Radiation Protection ◽  
Human Body ◽  
Radiation Safety ◽  
Radiological Protection ◽  
Surgical Practice ◽  
Anesthesia Practice ◽  
Dose Limits ◽  
Effects Of Radiation

Exposure to ionizing radiation is increasing in modern anesthesia practice, due to both the number of procedures facilitated and the expanding role of imaging in surgical practice. International Commission on Radiological Protection (ICRP) recommends that physicians who assist with radiation procedures be educated on the basics of radiation including units, effects of radiation exposure, and radiation protection for both providers and patients. This chapter will mirror the recommendations of the ICRP and include an introduction to radiation production, terminology, units, effects on the human body, dose limits, best practices for radiation protection, and safety infrastructure.

scholarly journals The relative contribution of shape and colour to object memory

2020 ◽  
Vol 48 (8) ◽  
pp. 1504-1521
Author(s):  
Irene Reppa ◽  
Kate E. Williams ◽  
W. James Greville ◽  
Jo Saunders
Keyword(s):  
Long Term Memory ◽  
Object Representations ◽  
Interference Effects ◽  
Practice Phase ◽  
Object Property ◽  
Relative Contribution ◽  
Induced Forgetting ◽  
New Evidence

AbstractThe current studies examined the relative contribution of shape and colour in object representations in memory. A great deal of evidence points to the significance of shape in object recognition, with the role of colour being instrumental under certain circumstances. A key but yet unanswered question concerns the contribution of colour relative to shape in mediating retrieval of object representations from memory. Two experiments (N=80) used a new method to probe episodic memory for objects and revealed the relative contribution of colour and shape in recognition memory. Participants viewed pictures of objects from different categories, presented one at a time. During a practice phase, participants performed yes/no recognition with some of the studied objects and their distractors. Unpractised objects shared shape only (Rp–Shape), colour only (Rp–Colour), shape and colour (Rp–Both), or neither shape nor colour (Rp–Neither), with the practised objects. Interference effects in memory between practised and unpractised items were revealed in the forgetting of related unpractised items – retrieval-induced forgetting. Retrieval-induced forgetting was consistently significant for Rp–Shape and Rp–Colour objects. These findings provide converging evidence that colour is an automatically encoded object property, and present new evidence that both shape and colour act simultaneously and effectively to drive retrieval of objects from long-term memory.

Long Term Maxillofacial Effects of Radiotherapy in Young Nasopharyngeal Carcinoma Patients: Report of 3 Cases

2013 ◽  
Vol 37 (4) ◽  
pp. 407-410 ◽  
Author(s):  
K Bektaş-Kayhan ◽  
CD Özbek ◽  
O Yazıcıoğlu ◽  
G Karagöz ◽  
M Altun ◽  
...  
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Stage Iv ◽  
Neck Region ◽  
Long Term Effects ◽  
Dental Clinics ◽  
Temporomandibular Joints ◽  
Effects Of Radiation

Nasopharyngeal carcinoma (NPC) is a rare and distinct malignancy that arises from the epithelium of the nasopharynx. It accounts almost 1 % of all pediatric malignancies. Oral complications of radiotherapy in the head and neck region are the result of the deleterious effects of radiation on salivary glands, oral mucosa, bone, dentition, masticatory musculature, and temporomandibular joints. Here we present 3 male NPC patients 13, 14 and 15 years old. One of them had stage III and the others stage IV diseases. Administered dose of radiation was 66 Gy for case I, 70 Gy for case II and 68 Gy for case III. The follow-up period was more than 12 months except for case III and all of them were disease free in their last visit. All attended dental clinics for dental and TMJ problems. Dentitions were severely affected, trismus and severe xerostomia. Long term effects of radiotherapy which has a great impact on patients’ quality of life and the role of supportive care and minimizing the late effects of ionizing radiation are discussed.

scholarly journals Photosynthesis is heavily chlororespiration-sensitive under fluctuating light conditions

2017 ◽  
Author(s):  
Wojciech J. Nawrocki ◽  
Felix Buchert ◽  
Pierre Joliot ◽  
Fabrice Rappaport ◽  
Benjamin Bailleul ◽  
...  
Keyword(s):  
Chlamydomonas Reinhardtii ◽  
Electron Flow ◽  
Redox Balance ◽  
Intermittent Light ◽  
Electron Transfer Pathway ◽  
Acceptor Side ◽  
Relative Contribution ◽  
Physiological Relevance

AbstractPhotosynthesis needs to adjust to dynamically changing light intensities in order to maximize its efficiency, notably by the employment of alternative electron pathways. One of them is chlororespiration - initially described in Chlamydomonas reinhardtii. This electron transfer pathway, found in all photosynthetic lineages, consists of a reduction of plastoquinone (PQ) through an NAD(P)H:PQ oxidoreductase and quinol (PQH2) oxidation by Plastid Terminal Oxidase, PTOX. Hence, chlororespiration constitutes an electron pathway potentially antagonistic to the linear photosynthetic electron flow from H2O to CO2. However, the limited flow chlororespiratory enzymes can sustain suggests that their relative contribution, at least in the light and in steady-state conditions, is insubstantial. Here, we focused on the involvement of PTOX in Chlamydomonas reinhardtii during transitions from dark to light and vice versa. We show that the kinetics of redox relaxation of the chloroplast in the dark was greatly affected when PTOX2, the major plastoquinol oxidase in Chlamydomonas, is lacking. Importantly, we show that this has a direct physiological relevance, as the growth of a PTOX2-lacking mutant is markedly slower in intermittent light. The latter can be rationalized in terms of a decreased flux sustained by photosystem II due to a redox limitation at the acceptor side of the PSI during the illumination periods. We finally show that the long-term regulation of cyclic electron flow around PSI is strongly affected in the PTOX2 mutant, substantiating an important role of chlororespiration in the maintenance of chloroplast redox balance.

scholarly journals Metrology for radiation protection: a new European network in the foundation phase

2021 ◽  
Vol 57 ◽  
pp. 1-7
Author(s):  
Annette Röttger ◽  
Attila Veres ◽  
Vladimir Sochor ◽  
Massimo Pinto ◽  
Michal Derlacinski ◽  
...  
Keyword(s):  
Medical Imaging ◽  
Ionizing Radiation ◽  
Radiation Protection ◽  
Activity Concentration ◽  
Medical Application ◽  
Ionising Radiation ◽  
High Dose ◽  
Natural Sources ◽  
The Mean

Abstract. More than 23 million workers worldwide are occupationally exposed to ionizing radiation and all people in the world are exposed to environmental radiation. The mean exposure, that is the mean annual dose of per person, is dominated by medical applications and exposure to natural sources. Due to recent developments in healthcare, e.g. the increasing application of ionising radiation in medical imaging with relative high doses like CT, and modern high dose applications (for example CT angiography), the exposure due to medical application has risen. Additionally, the changes in living conditions increase the exposure to natural radioactivity also: More living time is spent in buildings or in an urban environment, which causes higher exposure to Naturally Occurring Radioactive Materials (NORM) in building materials and higher exposure to radon. The level of radon activity concentration in buildings is far higher than in the environment (outdoor). This effect is often amplified by modern energy-efficient buildings which reduce the air exchange and thus increase the radon indoor activity concentration. In summary both medical application of ionizing radiation and natural sources are responsible for the increase of the mean annual exposure of the population. The accurate measurement of radiation dose is key to ensuring safety but there are two challenges to be faced: First, new standards and reference fields are needed due to the rapid developments in medical imaging, radiotherapy and industrial applications. Second, direct communication channels are needed to ensure that information on best practice in measurements reaches effectively and quickly the people concerned. It is therefore necessary to allow for an international exchange of information on identified problems and solutions. Consequently, a European Metrology Network (EMN) for radiation protection under the roof of EURAMET is in the foundation phase. This network EMN for Radiation Protection is being prepared by the project EMPIR 19NET03 supportBSS. The project aims to prepare this EMN by addressing this issue through the identification of stakeholder research needs and by implementing a long-term ongoing dialogue between stakeholders and the metrology community. The EMN will serve as a unique point of contact to address all metrological needs related to radiation protection and it will relate to all environmental processes where ionising radiation and radionuclides are involved. A Strategic Research Agenda and two roadmaps are in development, covering the metrology needs of both the Euratom Treaty and the EU Council Directive 2013/59/EURATOM pinning down the basic safety standards for protection against the dangers arising from exposure to ionizing radiation. Furthermore, long-term knowledge sharing, and capacity building will be supported and a proposal for a sustainable joint European metrology infrastructure is under way. This will significantly strengthen the radiation protection metrology and support radiation protection measures. The final goal of the network project is a harmonised, sustainable, coordinated and smartly specialised infrastructure to underpin the current and future needs expressed in the European regulations for radiation protection.

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