Ionising radiation exposure from medical imaging – A review of Patient's (un) awareness

Introduction: Medical imaging is the main source of artificial radiation exposure. Evidence, however, suggests that patients are poorly informed about radiation exposure when attending diagnostic scans. This review provides an overview of published literature with a focus on nuclear medicine patients on the level of awareness of radiation exposure from diagnostic imaging. Methods: A review of available literature on awareness, knowledge and perception of ionising radiation in medical imaging was conducted. Articles that met the inclusion criteria were subjected to critical appraisal using the Mixed Methods Appraisal Tool. Results: 140 articles identified and screened for eligibility, 24 critically assessed and 4 studies included in synthesis. All studies demonstrated that patients were generally lacking awareness about radiation exposure and highlighted a lack of communication between healthcare professionals and patients with respect to radiation exposure. Conclusion: Studies demonstrate a need to better inform patients about their radiation exposure, and further studies focusing on nuclear medicine patients are particularly warranted. Implications for practice: Adequate and accurate information is crucial to ensure the principle of informed consent is present

Spatio-temporal variability of acid sulphate soils in the plain of reeds, Vietnam : impact of soil properties, water management and crop husbandry on the growth and yield of rice in relation to microtopography

Acid sulphate soils in the Mekong delta cover 1.6 million hectares, of which 400 000 ha are located in the Plain of Reeds. Due to the presence of pyrite that yields acid when oxidised, all acid sulphate soils are (potentially) strongly acidic. Reclamation of the 150 000 ha of severely acid sulphate soils still uncultivated in 1990 became a national priority and now attracts local farmers and migrants. However, these soils present important agronomic problems and farmers urgently need advice to reclaim them. However, the development of recommendations and the cultivation of acid sulphate soils on a large scale are made difficult by their very high variability.The objectives of this thesis are to:characterise and explain spatio-temporal variability, at various scales, of acid sulphate soils and water in the Plain of Reeds, Vietnam;assess the impact of soil and water variability on rice cultivation;develop a simple model of rice yield build-up under conditions following land reclamation of severely acid sulphate soils in the Plain of Reeds;apply this model to identify and rank limiting factors, to precisely identify the optimal time window for cultivation and develop optimal agricultural practices (in particular water management and fertilisation) for the main cropping conditions found in the Plain of Reeds.Spatio-temporal variability in soil and water is very high, at all scales, as explained by the relative soil/water level which influences oxidation, and consequently the soil chemical status in the short term, and soil development in the long term. Soil microtopography is a key factor as slight differences in altitude induce important differences in intensity and length of soil oxidation and mineralisation. This resulted in the differentiation of two very different but closely intertwined soil types, separated by soils with intermediate characteristics. In the study area, located in the central part of the Plain of Reeds, organic Hydraquentic Sulfaquepts occupy locations below 75 cm above mean sea level where soil development is slow because of waterlogged conditions. Upon drainage, these soils are expected to develop into clayey Typic Sulfaquepts with jarosite and goethite mottles as found above 85 cm above mean sea level.Because of the high sensitivity of plants to soil chemical characteristics, water management which determines redox conditions and Fe and Al concentrations, is a key to the cultivation on acid sulphate soils. Unfortunately, the very high soil permeability makes water control very difficult, especially in the years immediately following reclamation. This makes it difficult to maintain good cropping conditions through irrigation or drainage. Consequently, the time window during which optimal cropping conditions are met is very short. Its starting date and duration are also spatially variable, in relation to microtopography. To extend this time window, farmers in the Plain of Reeds start cultivation as soon as possible, broadcasting pregerminated rice seeds in flood water, before it has completely receded. In these cropping conditions, farmer-managed trials were conducted for four years, after precise site characterisation (using geostatistical methods). Detailed studies of crop phenology and yield led to the development of a semi-quantitative model of rice yield build-up. Yield is mainly determined by panicle density and plant growth, reflected in the weight of one grain.Within fields, plant, tiller and panicle densities are linearly correlated to microtopography. This has been explained by higher plant mortality and poorer tillering in low positions due to deeper and longer submersion which reduces light intensity, but also to action of sulphate-reducing bacteria in the deeply reduced conditions of the lowest positions. Plant growth can be affected by the deep reduction inducing iron toxicity in the lowest locations. It is, however, mainly limited by aluminium toxicity linked to acidification of the high positions in oxidised conditions at the end of the growing season. This results in plant growth and yield correlated to microtopography in a quadratic trend, with maximum growth at medium topographic level, and with a strong decrease at high topographic levels.Between fields, similar correlations are observed in the first year after reclamation. With cultivation, improvement of water control results in yield increase every year. This increase is faster on high fields, in which better plant growth can be obtained together with high densities. Thus, after 3 years, average yields of the fields become linearly correlated with the average topographic level, with maximum values at high topographic levels.Application of this model allows the improvement of water management strategies, based on field characteristics: it determines the proper timing for sowing pregerminated seeds and optimal water management practices, as a function of field topography and age, and flood characteristics.High fields (higher than 85 cm above mean sea level), and to a certain extend fields at medium topographic level, mainly suffer from acidification at the end of the growth cycle. Water management on these soils should aim at maintaining wet soil to avoid oxidation. In this respect, early sowing, in deep water (30 to 35 cm) is required in the first year after reclamation. Although this leads to lower densities, it is the only way to maintain wet conditions until the end of the cycle and to allow acceptable plant growth. With improvement of water control, sowing can be progressively delayed, until sowing on wet soil becomes possible. In contrast to this situation, low fields (lower than 75 cm above mean sea level) suffer from submersion and deep reduction. Water management should aim at creating a slight oxidation of the top soil as soon as possible. The best practice consists of sowing on wet soil after pumping water out of the field, which is not always possible in the first year after reclamation because of the high permeability.The model also allows identification of sources of variability in fertiliser experiments conducted on these soils. The advantages of thermophosphate fertiliser over Di-Ammonium phosphate are shown and explained.Tools and methods to control variability and to use it as information are also presented, such as the use of correlations between microtopography, soil types and natural vegetation for mapping, the proper design and set up of experiments upon precise characterisation of fields and the use of co-variance analysis with microtopography as a covariate.The results of the study are meaningful to farmers as well as policy makers, and provide a semi-quantitative picture of the dynamics, risks and opportunities for reclamation and agricultural use of acid sulphate soils in the Plain of Reeds and beyond.</p

Personality, health behaviors and quality of life among colorectal cancer survivors:Results from the PROFILES registry

Contains fulltext : 170340.pdf (Publisher’s version ) (Open Access)PURPOSE: There is a paucity of research looking into the relationship between personality and health behaviors among cancer survivors. The aim of this study was to investigate whether Type D personality and its two constituent components, negative affectivity (NA) and social inhibition (SI), are associated with health behaviors, quality of life (QoL), and mental distress among colorectal cancer (CRC) survivors. METHODS: A population-based study was conducted among 2,620 CRC patients diagnosed between 2000 and 2009, who completed measures of personality (DS14), health behaviors, QoL (EORTC QLQ-C30), and mental distress (hospital anxiety and depression scale). RESULTS: Personality was not associated with body mass index or smoking. Those scoring high on NA (with or without SI) were more often nondrinkers and less physically active compared to those scoring high on neither or only SI. Personality (high scores NA) and health behaviors (inactivity) were independently associated with poor QoL and mental distress. CONCLUSIONS: CRC survivors with high scores on NA are at risk of being inactive and have worse health outcomes

Radiation exposure awareness from patients undergoing nuclear medicine diagnostic 99mTc-MDP bone scans and 2-deoxy-2-(18F) fluoro-D-glucose PET/computed tomography scans

INTRODUCTION: Medical imaging is on average the largest source of artificial radiation exposure worldwide. This study seeks to understand patient's awareness of radiation exposure derived from nuclear medicine diagnostic scans and assess if current information provided by leaflets is adequate. METHODS: Single-centre cross-sectional questionnaire study applied to bone scan and FDG PET/computed tomography patients, at a nuclear medicine and PET/computed tomography department over a 15-week period in 2018. Questionnaires on dose comparators were designed in collaboration with patients, public, and experts in radiation exposure. Qualitative data were analysed using thematic analysis and quantitative data using SPSS (V. 24). RESULTS: A total of 102 questionnaires were completed (bone scan = 50; FDG PET/computed tomography = 52). Across both groups, 33/102 (32.4%) patients reported having a reasonable understanding of nuclear medicine and 21/102 (20.6%) reported a reasonable knowledge of ionising radiations. When asked to compare the exposure dose of respective scans with common comparators 8/50 (16%) of bone scan patients and 11/52 (21.2%) FDG PET/computed tomography answered correctly. On leaflet information, 15/85 (17.6%) patients reported the leaflets do not provide enough information on radiation exposure and of these 10/15 (66.7%) commented the leaflets should incorporate more information on radiation exposure dose. CONCLUSION: More observational and qualitative studies in collaboration with patients are warranted to evaluate patients' understanding and preferences in communication of radiation exposure from nuclear medicine imaging. This will ensure communication tools and guidelines developed to comply with ionising radiation (medical exposure) regulation 2017 are according to patients needs and preferences

Negative illness perceptions are related to poorer health‐related quality of life among thyroid cancer survivors:Results from the PROFILES registry

Background Differentiated thyroid cancer (DTC) reports a poorer health‐related quality of life (HRQoL) than a norm population. Patients' illness perceptions are modifiable and known associates of HRQoL in other cancers. The aim was to examine the relationship between illness perceptions and HRQoL among DTC survivors. Methods DTC survivors registered in the Netherlands Cancer Registry diagnosed between 1990 and 2008, received a survey on illness perceptions (Brief‐Illness Perception Questionnaire; B‐IPQ) and HRQoL (European Organisation for Research and Treatment of Cancer, Quality of Life Questionnaire‐Core 30; EORTC QLQ‐C30). Multiple regression analyses were conducted investigating the relation between illness perceptions and HRQoL, while controlling for sociodemographic and clinical characteristics. Results Two hundred and eighty‐four DTC survivors were included. DTC survivors who believed their illness had many negative consequences; who perceived their illness as controllable by treatment; who had strong beliefs symptoms could be attributed to their illness; and who had strong beliefs their illness causes negative emotions, reported a poorer HRQoL. Conclusions Stronger negative illness perceptions are related to a poorer HRQoL among DTC survivors

Having co-morbid cardiovascular disease at time of cancer diagnosis:Already one step behind when it comes to HRQoL?

Background The relation between cardiovascular disease (CVD) present at the time of cancer diagnosis and Health-Related Quality of Life (HRQoL) assessed years after cancer diagnosis has – to our knowledge – not been studied. The objective is, therefore, to examine the relation between co-morbid CVD at cancer diagnosis and HRQoL among cancer survivors diagnosed with colorectal, thyroid, prostate, endometrium, ovarian cancer, melanoma, (non-)Hodgkin lymphoma, chronic lymphocytic leukemia (CLL), or multiple myeloma (MM) in an exploratory population-based cross-sectional study. Material and methods Analyses were performed on combined data sets from the PROFILES and Netherlands Cancer Registry (NCR). Data on co-morbid CVD at cancer diagnosis was extracted from the NCR. HRQoL was measured via PROFILES at a median of 4.6 years after cancer diagnosis. General Linear Model Analyses were run for the total group of cancer survivors and for each malignancy. Results In total, 5930 cancer survivors (2281 colorectal, 280 thyroid, 1054 prostate, 177 endometrium, 389 ovarian cancer, 212 melanoma, 874 non-Hodgkin and 194 Hodgkin lymphoma, 242 CLL, and 227 MM survivors) were included. For the total group, survivors who had a CVD at cancer diagnosis (n = 1441, 23.4%) reported statistically significant and clinically important lower scores on global QoL and physical functioning and higher scores for dyspnea (p < .05) compared to those without CVD. Co-morbid CVD at cancer diagnosis was negatively related to global QoL, the five functional scales and the symptoms fatigue and dyspnea across most malignancies (i.e., colorectal, and prostate cancer, non-Hodgkin lymphoma, ovarium cancer, melanoma, and CLL). No significant relations were found among thyroid and endometrium cancer, Hodgkin lymphoma and MM survivors, likely due to small numbers. Conclusion In conclusion, co-morbid CVD at cancer diagnosis was negatively related to HRQoL, especially to global QoL, physical and role functioning, and the symptoms fatigue and dyspnea

Генетический полиморфизм клонов и их семенного потомства в архивно-клоновой плантации плюсовых деревьев сосны обыкновенной

Изучена генетическая изменчивость по 12 аллозимным локусам (10 полиморфных) архивно-клоновой плантации 23 плюсовых деревьев Pinus sylvestris L. и их семенного потомства на юго-востоке Украины. Более половины клонов имели 4–8 гетерозиготных локусов, а их семенное потомство отличалось меньшим уровнем изменчивости, чем материнские растения. Семенное потомство получено от высокой доли ауткроссинга (tm = = 95 %). Для потомства клонов характерна повышенная доля нарушений сегрегации аллелей в мегагаметофитах и высокая встречаемость существенных отклонений в распределении генотипов зародышей семян от теоретически ожидаемого согласно закону Харди Вайнберга.Досліджено генетичну мінливість за 12 алозимними локусами (10 поліморфних) архівно-клонової плантації 23 плюсових дерев Pinus sylvestris L. та їх насіннєвого потомства на південному сході України. Понад половина клонів мали 4–8 гетерозиготних локусів, а їх насіннєве потомство відрізнялося нижчим рівнем мінливості, ніж материнські рослини. Насіннєве потомство отримано від високої частки ауткросинга (tm = 95 %). Для потомства клонів характерна підвищена частка порушень сегрегації алелів у мегагаметофітах і висока частота відхилень розподілу генотипів зародків насіння від очікуваного згідно з законом Харді-Вайнберга.Genetic variation at 12 allozyme loci (10 of them being polymorphic ones) has been studied in the archive-clone plantation of 23 Pinus sylvestris plus-trees and their seed progeny in the south-east of Ukraine. More than a half of clones had 4–8 heterozygous loci, whereas their seed progeny was marked by a lower variation than maternal trees. Seed progeny was obtained at a high outcrossing rate (tm= 95 %). The clone progeny was characterized by a high percentage of abnormal allele segregation in megagametophytes. There was also a high frequency of significant deviation in distribution of seed embryo genotypes from the theoretically expected one according to the Hardy-Weinberg law

Place et rôle du riz pluvial dans les systèmes de production du lac Alaotra Les systèmes SCV (semis direct sur couverture végétale permanente) : une alternative viable pour une agriculture pluviale durable

La région de l'Alaotra repose sur un plateau situé à 750 mètres d'altitude avec au cœur de la plaine le lac Alaotra. La surface cultivée en riziculture est estimée à 148 500 ha en 2000 (FAO/UPDR, 2000), dont 75-80 000 ha dans la cuvette du Lac et plus de 65-70 000 ha au sud et dans les zones en périphérie, qui constitue 10% de la surface rizicole nationale pour seulement 4% des riziculteurs malgaches. Cette région réalise 33% de la valeur ajoutée de l'ensemble de la filière nationale et 15% de la richesse générée par le secteur riz. Le climat irrégulier constitue une contrainte majeure pour tous les agriculteurs du lac Alaotra. Les relations agriculture-élevage sont au cœur de la problématique de développement et d'évolution des exploitations agricoles.Ainsi, avec la saturation des rizières irrigables ou à Mauvaise Maîtrise de l'Eau (RMME), la colonisation agricole des tanety anciennement dévolus aux pâturages extensifs depuis les années 1980 s'est accélérer, induisant la perturbation des activités d'élevage bovin traditionnel extensif à objectif de capitalisation qui évoluent aujourd'hui vers un élevage productif (embouche et production laitière) ou de trait. Le diagnostic réalisé en 2007 a mis en évidence 7 types d'exploitations agricoles différents. Les différents systèmes de riziculture pluviale se retrouvent sur les plateaux sommitaux et les pentes des collines (en rotation jachère culture sur les sols très pauvres), les bas de pente et les baiboho, en rotation avec d'autres cultures pluviales (maïs, manioc, pois de terre...) avec ou sans jachère, ou en système SCV depuis leur introduction au début des années 2000. L'introduction de variétés composites poly-aptitudes de type Sebota a pu lever une contrainte majeure des zones ni totalement irriguées ni totalement pluviales mais intermédiaires dans les RMME (riziculture pluviale partiellement irriguée, selon l'accès à l'eau et les caractéristiques climatiques de la saison), Les systèmes SCV mis au point sur baiboho avec des successions culturales de type riz de saison / haricot de contre saison - maïs de saison ou riz de saison puis vesce de contre saison associée ou non à des cultures maraîchères montrent également un niveau de production et de sécurité par rapport aux aléas climatiques très proche voire supérieurs à ceux obtenus en riziculture irriguée. La part du riz pluvial dans la formation du revenu et la sécurité alimentaire a été analysée pour chaque type d'exploitation et varie de 20 à 30 % du revenu riz total (avant autoconsommation), et se révèle croissante en fonction du rapport tanety / rizière dans l'exploitation. Ainsi, sur certaines zones, le riz pluvial semble avoir de beaux jours devant lui