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Inductively coupled plasma mass spectrometry (ICP-MS) techniques are widely used for determination of long-lived radionuclides and their isotopic ratios in the nuclear fields. Uranium (U) and Plutonium (Pu) isotopes have been determined by many researchers with ICP-MS due to its relatively high sensitivity and short measurement time. In this work, an inter-laboratory comparison exercise among the Nordic countries was performed, focusing on the measurement of U and Pu isotopes in certified reference materials by ICP-MS. The performance and characters of different ICP-MS instruments are evaluated and discussed in this paper.

Dynamic transfer of radionuclides to fish was studied in a series of experiments under field condition in two lakes within the Chernobyl exclusion zone during 2016-2020. "Clean" common rudd (Scardinius erythrophthalmus) and silver Prussian carp (Carassius gibelio) were transported to the contaminated Glubokoye Lake and kept in cages during several months of exposure, while contaminated Glubokoye fish were kept in cages in the "clean" Starukha Lake. Radiocaesium (137Cs) and radiostrontium (90Sr) were determined in intestine contents, muscle and bone tissues based on repeated samples during several months of exposure. During summer, the activity concentrations of 137Cs and 90Sr increased with time of exposure in clean fish caged in the contaminated lake. During autumn and winter, however, minor changes in fish uptake occurred during several weeks of exposure to the contaminated water. Furthermore, depuration in the contaminated fish was significant during summer, while insignificant during winter when exposed in the «clean» water. The rate constant of 137Cs uptake in muscle was between 8.0 and 22 day-1 during summer, while 0.2 to 1.0 day-1 during autumn-winter. Similarly, the rate constant of 90Sr uptake in bone was between 1.4 and 1.6 day-1, while 0.08-0.52 day-1 during autumn-winter. Biological half-lives of 137Cs in fish muscle tissue in summer were 77 ± 10 days, while exceeded 230 days during seasons at low water temperature. The results demonstrated that the transfer of 137Cs and 90Sr to fish was highly dependent upon seasons, in particular the water temperature. The transfer data obtained during low water temperature seasons deviated significantly from transfer data in literature and handbooks. Thus, seasonal changes in radionuclide transfer to fish should be taken into account when radiological impact to fish is assessed.

High concentrations of cadmium in brown crab are an issue of food safety, and large variations between different areas have been found. To investigate the relative importance of dietary and aqueous uptake regarding the overall accumulation in brown crab, we used stable isotopes to trace the uptake from both routes simultaneously in the same animals. We demonstrated that the analytical challenges regarding background concentrations of natural isotope distribution and polyatomic interferences in the different matrices can be overcome with an appropriate analytical setup and modern mathematical corrections using a computer software. Cadmium was accumulated via both routes and was found in all measured organs at the end of the exposure phase. The obtained data were used to establish accumulation curves for both uptake routes and estimate accumulation parameters for hepatopancreas, as the most important organ in crab regarding total cadmium body burden. Using the estimated parameters in combination with naturally relevant cadmium concentrations in seawater and diet in a model, allowed us to predict the relative importance of the aqueous and dietary uptake route to the total hepatopancreas burden. According to the prediction, the dietary route is the main route of uptake in brown crab with a minimum of 98% of the accumulated cadmium in hepatopancreas originating from diet. Future studies addressing the source and accumulation of cadmium in crab should therefore focus on the uptake from feed and factors connected to foraging. publishedVersion

Exogenously administered B-type natriuretic peptide (BNP) has been shown to offer cardioprotection through activation of particulate guanylyl cyclase (pGC), protein kinase G (PKG) and KATP channel opening. The current study explores if cardioprotection afforded by short intermittent BNP administration involves PI3K/Akt/p70s6k dependent signaling, and whether this signaling pathway may participate in regulation of BNP mRNA expression at early reperfusion. Isolated Langendorff perfused rat hearts were subjected to 30 min of regional ischemia and 120 min of reperfusion (IR). Applying intermittent 3 × 30 s infusion of BNP peptide in a postconditioning like manner (BNPPost) reduced infarct size by >50% compared to controls (BNPPost 17 ± 2% vs. control 42 ± 4%, p < 0.001). Co-treatment with inhibitors of the PI3K/Akt/p70s6k pathway (wortmannin, SH-6 and rapamycin) completely abolished the infarct-limiting effect of BNP postconditioning (BNPPost + Wi 36 ± 5%, BNPPost + SH-6 41 ± 4%, BNPPost + Rap 37 ± 6% vs. BNPPost 17 ± 2%, p < 0.001). Inhibition of natriuretic peptide receptors (NPR) by isatin also abrogated BNPPost cardioprotection (BNPPost + isatin 46 ± 2% vs. BNPPost 17 ± 2%, p < 0.001). BNPPost also significantly phosphorylated Akt and p70s6k at early reperfusion, and Akt phosphorylation was inhibited by SH-6 and isatin. Myocardial BNP mRNA levels in the area at risk (AA) were significantly elevated at early reperfusion as compared to the non-ischemic area (ANA) (Ctr(AA) 2.7 ± 0.5 vs. Ctr(ANA) 1.2 ± 0.2, p < 0.05) and the ischemic control tissue (Ctr(AA) 2.7 ± 0.5 vs. ischemia 1.0 ± 0.1, p < 0.05). Additional experiments also revealed a significant higher BNP mRNA level in ischemic postconditioned (IPost) hearts as compared to ischemic controls (IPost 6.7 ± 1.3 vs. ischemia 1.0 ± 0.2, p < 0.05), but showed no difference from controls run in parallel (Ctr 5.4 ± 0.8). Akt inhibition by SH-6 completely abrogated this elevation (IPost 6.7 ± 1.3 vs. IPost + SH-6 1.8 ± 0.7, p < 0.05) (Ctr 5.4 ± 0.8 vs. SH-6 1.5 ± 0.9, p < 0.05). In conclusion, Akt dependent signaling is involved in mediating the cardioprotection afforded by intermittent BNP infusion at early reperfusion, and may also participate in regulation of reperfusion induced BNP expression. publishedVersion

Background The incidence of atopic dermatitis, wheezing, asthma and allergic rhinoconjunctivitis have been increasing. Register-based studies are essential for research in subpopulations with specific diseases, and facilitate epidemiological studies to identify causes and evaluate interventions. Algorithms have been developed to identify children with atopic dermatitis, asthma or allergic rhinoconjunctivitis using register information on disease-specific dispensed prescribed medication and hospital contacts, but the validity of the algorithms has not been evaluated. The present study validated the algorithms versus gold standard deep telephone interviews with the caretaker about physician-diagnosed atopic dermatitis, wheezing, asthma, or allergic rhinoconjunctivitis in the child. Methods The algorithms defined each of the three atopic diseases using register-based information on disease specific hospital contacts and/or filled prescriptions of disease specific medication. Confirmative answers to questions about physician-diagnosed atopic disease were used as the gold standard for the comparison with the algorithms, resulting in sensitivities and specificities and 95% confidence intervals. The interviews with the caretaker of the included 454 Danish children born 1997-2003 were carried out May-September 2015; the mean age of the children at the time of the interview being 15.2 years (standard deviation 1.3 years). Results For the algorithm capturing children with atopic dermatitis, the sensitivity was 74.1% (95-% confidence interval: 66.9-80.2%) and the specificity 73.0% (67.3-78.0%). For the algorithm capturing children with asthma, both the sensitivity of 84.1% (78.0-88.8%) and the specificity of 81.6% (76.5-85.8%) were high compared with physician-diagnosed asthmatic bronchitis (recurrent wheezing). The sensitivity remained high when capturing physician-diagnosed asthma: 83.3% (74.3-89.6%), however, the specificity declined to 66.0% (60.9-70.8%). For allergic rhino-conjunctivitis, the sensitivity was 84.4% (78.0-89.2) and the specificity 81.6% (75.0-84.4). Conclusion The algorithms are valid and valuable tools to identify children with atopic dermatitis, wheezing, asthma or allergic rhinoconjunctivitis on a population level using register data. This article is protected by copyright. All rights reserved.

Objectives Estimating associations between somatic and socioeconomic risk factors and post-discharge under-five mortality. Design Register-based national cohort study using multiple Cox regression. Participants The population of 1,263,795 Danish children live-born 1997-2016 who survived until date of first discharge to the home after birth was followed from that date until death, emigration, 5 years of age or 31 December 2016. Main outcome measures (A) Mortality hazard ratios (HRs) among all children, (B) mortality HRs among children without severe chronic disease, and (C) mortality HRs among children without severe chronic disease or asthma. Main results In the total population (1,947 deaths) severe chronic disease was associated with mortality HR = 15.28 (95% CI: 13.77-16.95). In children without severe chronic-disease (719 deaths) other somatic risk factors were immature birth HR = 3.40 (1.92-6.02), maternal smoking HR = 1.84 (1.55-2.18) and low birth weight HR = 1.74 (1.21-2.51). Socioeconomic risk factors for mortality included: maternal age < 25 years HR = 1.91 (1.38-2.64) compared to > 35 years (similar for 30-35 years and 25-29 years), lowest vs. highest family income tertile HR = 1.76 (1.23-2.51), not living with both parents HR = 1.63 (1.25-2.13), maternal unemployment HR = 1.54 (1.12-2.12), presence of siblings HR = 1.44 (1.20-1.71) and secondary vs. tertiary parental education HR = 1.33 (1.07-1.65) for fathers and HR = 1.23 (1.01-1.52) for mothers. Factors not found to be associated with child mortality in this population included presence of asthma HR = 1.29 (0.83-1.98) and non-Danish ethnicity HR = 0.98 (0.70-1.37). Conclusions Childhood death after discharge to the home after birth and before 5 years of age is a very rare event in Denmark. This 'post-discharge' mortality was heavily associated with severe chronic disease. In children without severe chronic disease, immature birth, maternal smoking and certain socioeconomic characteristics were noticeable risk factors. Mortality may possibly be decreased by focusing on vulnerable groups.

Master i rettsvitenskap JUS399 MAJUR

The present disclosure relates to a solution comprising a water insoluble carbohydrate and a radionuclide chelated by a hydrophobic chelator, wherein the solution sets under aqueous conditions, such as in vivo, to form e.g. a gel, a semi-solid, a solid, a crystal or any mixtures thereof. The disclosure further relates to preparation of such solution and use of such solution for brachytherapy and/or guidance of surgery.

Inductively coupled plasma (ICP) spectrometry techniques are widely used in the fields related to environmental monitoring, nuclear waste disposal and management, radioecology and tracer studies, as well as nuclear forensics and nuclear emergency preparedness. Especially ICP mass spectrometry (ICP-MS) is playing an important role for determination of low-level long-lived radionuclides and their isotopic ratios. ICP optical emission spectrometry (ICP-OES) is commonly used for determining stable elements (Al, Fe, Ca, etc.) and cannot perform isotopic ratio measurement with desirable precision and at low analyte concentrations. Therefore ICP-OES is often used as a supplementary technique to ICP-MS in the analysis, for instance, to screen the matrix composition of a sample, or to determine Sr and Y chemical yield in the Sr-90 analysis, etc. Among the Nordic countries, there are probably less than 20 ICP-MS instruments which are currently applied in the nuclear field for the measurement of radionuclides and their isotopic ratios. Due to different application purposes and technical background of the analysts, each ICP lab has different set-ups and experiences in running these instruments. More efficient application of ICP-MS will be achieved when these experiences are well shared among these labs. Also, for newly established ICP labs or scientists/students in the Nordic countries to quickly build up the competence in operating their instruments in practice, hands-on experience is very valuable. Therefore, within the Nordic-ICP project, an inter-comparison exercise was performed during 2016, which was focused on the measurement of uranium and plutonium isotopes in certified reference material by ICP-MS in combination with radiochemical separation. This report summarizes the results and conclusions obtained base on this inter-comparison exercise.

The present invention relates to cationic micelles, and in particular the compounds capable of forming such cationic micelles for use in cell tracking.

The present disclosure relates to a solution comprising a water insoluble carbohydrate and a fluorescent dye, such as a near infrared (NIR) contrast agent, wherein the solution sets under aqueous conditions, such as in vivo, to form e.g. a gel, a glass, a semi-solid, a solid, a crystal or any mixtures thereof. The disclosure further relates to preparation of such solution and use of such solution for in vivo imaging and/or guidance of surgery or interventional therapeutic procedures.

The ICP User seminar was held at Risø, Denmark, during 25-27 September 2017. The seminar consisted of 2-day lectures given by six invited professionals and thirteen seminar participants, as well as 1-day lab training by invited expert. The lectures covered different topics including theoretical principles of ICP, methodology development and application of ICP techniques for different isotopes/isotopic ratios, recent development of new ICP technology and its application, etc. The results obtained from the inter-comparison exercise 2016 were presented and discussed. The lab training covered demonstration of the operation of ICP-MS, software and technical instructions. The seminar was attended by 51 individuals from 26 organisations.

The present invention provides novel PSMA targeting urea-based ligands that binds to prostate‐specific membrane antigen (PSMA) which is expressed 8-to-12-fold higher in prostate cancer cells when compared to healthy tissue. The PSMA targeting urea-based ligands comprises a chelating agent that may comprise a metal and a halogen radioisotope of fluorine, iodine, bromine or astatine. The invention further relates to a method for providing the PSMA targeting urea-based ligands of the invention, to precursors of the PSMA targeting urea-based ligands and to the PSMA targeting urea-based ligands use in radiotherapy, imaging and theranostic.