Practical recommendations for radium-223 treatment of metastatic castration-resistant prostate cancer

is the first targeted alpha therapy for patients with castration resistant prostate cancer and symptomatic bone metastases. Radium-223 provides a new treatment option for this setting, but also necessitates a new treatment management approach. We provide straightforward and practical recommendations for European nuclear medicine centres to optimize radium-223 service provision. Methods An independent research consultancy agency observed radium-223 procedures and conducted interviews with all key staff members involved in radium-223 treatment delivery in 11 nuclear medicine centres across six countries (Germany, Italy, the Netherlands, Spain, Switzerland and the UK) experienced in administering radium-223. The findings were collated and discussed at a meeting of experts from these centres, during which key consensus recommendations were defined. Results The recommendations cover centre organization and preparation; patient referral; radium-223 ordering, preparation and disposal; radium-223 treatment delivery/administration; and patient experience. Guidance includes structured coordination and communication within centres and multidisciplinary teams, focusing on sharing best practice to provide high quality, patient-centred care throughout the treatment pathway. Conclusions These expert recommendations are intended to complement existing management guidelines. Sharing best practice and experience will help nuclear medicine centres to optimize radium-223 service provision and improve patient care

Multiple training interventions significantly improve reproducibility of PET/CT-based lung cancer radiotherapy target volume delineation using an IAEA study protocol

AbstractBackground and purposeTo assess the impact of a standardized delineation protocol and training interventions on PET/CT-based target volume delineation (TVD) in NSCLC in a multicenter setting.Material and methodsOver a one-year period, 11 pairs, comprised each of a radiation oncologist and nuclear medicine physician with limited experience in PET/CT-based TVD for NSCLC from nine different countries took part in a training program through an International Atomic Energy Agency (IAEA) study (NCT02247713). Teams delineated gross tumor volume of the primary tumor, during and after training interventions, according to a provided delineation protocol. In-house developed software recorded the performed delineations, to allow visual inspection of strategies and to assess delineation accuracy.ResultsFollowing the first training, overall concordance indices for 3 repetitive cases increased from 0.57±0.07 to 0.66±0.07. The overall mean surface distance between observer and expert contours decreased from −0.40±0.03cm to −0.01±0.33cm. After further training overall concordance indices for another 3 repetitive cases further increased from 0.64±0.06 to 0.80±0.05 (p=0.01). Mean surface distances decreased from −0.34±0.16cm to −0.05±0.20cm (p=0.01).ConclusionMultiple training interventions improve PET/CT-based TVD delineation accuracy in NSCLC and reduce interobserver variation

ENERGY BUDGETS IN FREE-LIVING GREEN IGUANAS IN A SEASONAL ENVIRONMENT

Using a variety of techniques we estimated energy expenditure and allocation of energy in free-living green iguanas (Iguana iguana) in a seasonal environment on Curacao, Netherlands Antilles. 1) Daily energy expenditure (DEE) was measured by means of the doubly labeled water (DLW) technique, using O-18 and deuterium (H-2). The method was validated in green iguanas at ambient temperature and humidity levels occurring on Curacao. Energy expenditures from the DLW method differed by 2.1 +/- 8.2% compared to respirometry and balance methods. This value falls within the range of deviations found in other validation studies, and indicates that the DLW method is acceptable in green iguanas even at high ambient humidity. 2) Average DEE was 71.7 kJ . kg-1.d-1. There were no significant differences in DEE between males and females, although males tended to have higher metabolic rates during the mating season. Energy expenditure on a yearly basis including clutch production in females did not differ between females and males, indicating comparable annual levels of energy expenditure between the sexes. 3) Temperature dependence of standard metabolic rate (SMR) and resting metabolic rate (RMR) were determined by respirometry experiments. RMR increased with temperature with a Q10 of 2.24. In combination with field body temperatures SMR and RMR of free-living iguanas could be determined. SMR amounted to 15-22% of the DEE. DEE was 1.8-2.8 times RMR. 4) The energy expenditure above RMR was allocated between activities involving locomotion and stationary activities. DEE in combination with behavioral data revealed an indirect measure of the costs linked to locomotion in the field, including climbing (255 kJ.km-1.kg-1). Locomotion with a climbing component imposed six times the costs of horizontal walking. Although time spent locomoting was only a very small fraction of the total time, the costs linked to locomotor activities amounted to almost-equal-to 23% of the daily energy expenditure. Postural adjustment costs were almost-equal-to 33% of the DEE. Locomotion could explain 78% of the observed variation in DEE. If other activities, such as foraging and social activities, were included in multiple regression analyses, 96% of the variation in DEE could be explained. 5) Body condition of males decreased during the mating period (March/April), while most of the decrease in body condition of females occurred during the time of oviposition (May/June). Time spent in social activities was higher during the mating period, especially so in males, but time devoted to other activities (locomotion, foraging) did not differ significantly between the seasons. Comparison between the sexes revealed that males spent more time locomoting than females, throughout the year. 6) Differences in body condition in the course of the year were not due to differences in DEE, but were mainly a result of differences in metabolizable energy intake. Though on a yearly basis energy expenditure was equal in both sexes, energy allocation differed between the sexes. Females devoted almost-equal-to 15% of their annual energy budget to the production of eggs, while males showed heightened social activity during the mating phase and spent twice as much time in locomotor activities than females

Does abscisic acid affect strigolactone biosynthesis?

Strigolactones are considered a novel class of plant hormones that, in addition to their endogenous signalling function, are exuded into the rhizosphere acting as a signal to stimulate hyphal branching of arbuscular mycorrhizal (AM) fungi and germination of root parasitic plant seeds. Considering the importance of the strigolactones and their biosynthetic origin (from carotenoids), we investigated the relationship with the plant hormone abscisic acid (ABA). Strigolactone production and ABA content in the presence of specific inhibitors of oxidative carotenoid cleavage enzymes and in several tomato ABA-deficient mutants were analysed by LC-MS/MS. In addition, the expression of two genes involved in strigolactone biosynthesis was studied. * • The carotenoid cleavage dioxygenase (CCD) inhibitor D2 reduced strigolactone but not ABA content of roots. However, in abamineSG-treated plants, an inhibitor of 9-cis-epoxycarotenoid dioxygenase (NCED), and the ABA mutants notabilis, sitiens and flacca, ABA and strigolactones were greatly reduced. The reduction in strigolactone production correlated with the downregulation of LeCCD7 and LeCCD8 genes in all three mutants. * • The results show a correlation between ABA levels and strigolactone production, and suggest a role for ABA in the regulation of strigolactone biosynthesis