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The systematic quality assurance (QA) and control of testing methods in incorporation monitoring consists of continual measures for internal QA and additional measures such as external laboratory controls. This includes among other aspects accuracy, precision and descriptions of the methods as well as the representation and timely availability of analytic results of measurements and internal dose assessment. At the officially recognised incorporation measurement office at Jülich, QA is performed for direct measurements (whole-body counter), indirect measurements with radiochemical testing methods of excretion samples and internal dose assessment. [ABSTRACT FROM PUBLISHER]

The accreditation of the Competent Incorporation Measuring Body at Jülich includes incorporation monitoring by means of direct measurements of the body activity as well as by means of indirect determination of the body activity by radiochemical analysis of excreta samples. In both testing areas, it proved to be very useful to have a flexible scope. In particular, the associated freedom in choosing testing procedures supports the continual improvement process of the laboratory. The modification of existing methods as well as the development and introduction of new procedures makes an immediate reaction to changed requirements feasible. At Jülich the use made out of the flexible scope included, e.g. the introduction of mathematical calibration in whole-body counting and the automation of sample preparation in radiochemical analysis. Advantages of the new procedures and modified methods include on the one hand the reduction of processing times, downtimes and hazard potentials on the other hand enhanced detection limits and improved cost-efficiency. In the result, it can be recommended to other qualified testing laboratories to go for a flexible scope. [ABSTRACT FROM PUBLISHER]

It is shown how the decision threshold, the detection limit and the limits of a coverage interval -- summarily called the characteristic limits -- and, in addition, the best estimate and the associated standard uncertainty of a non-negative radiation measurand are to be calculated by using the Monte Carlo (MC) method in ionising-radiation measurements. The limits are mathematically defined by means of quantiles of the Bayesian distributions of the possible measurand values. The MC-induced uncertainties of the limits and typical problems connected with MC application are also treated. The paper can serve as a bridge between the ISO Guide to the Expression of Uncertainty in Measurement (GUM), Supplement 1 applying the MC method and ISO/FDIS 11929 (at present in preparation) dealing with the characteristic limits. As an illustration, a net count rate measurand, being the difference of a gross and a background count rate, is treated theoretically and numerically. More complex examples deal with the wipe test for surface contamination and with a linear multi-channel spectrum unfolding. [ABSTRACT FROM AUTHOR]

After the Chernobyl reactor accident wide areas of Belarus were contaminated with radioactive fallout. The verification and documentation of the long-term development of radiation doses is still going on. A population group of special concern are the children living in contaminated regions. The annual dose limit of 1 mSv is still exceeded in some cases, essentially due to high body burdens of 137Cs as indicated by screening measurements with portable incorporation monitors. In this situation the evaluation of possible dose reduction measures in addition to the control of food contamination is being investigated. Special attention is given to the therapeutic application of a pectin preparation (Vitapect), for which a dose-lowering effect is presumed by Belarusian scientists. In a placebo-controlled double-blind study, several groups of contaminated children received a pectin compound named Vitapect for a two-week period during their stay in a sanatorium. For comparison the same number of control groups were given a placebo preparation. The 137Cs body burden of the children was measured at the beginning and the end. The mean relative reduction of the specific activity within the Vitapect groups was found to be ~33%, whereas the specific activity of the children who received a placebo decreased only by ~14%, due to clean food supply. It is known that pectins chemically bind cations like caesium in the gastrointestinal tract and thereby increase faecal excretion. Theoretical calculations based on this assumption and considering metabolism processes are qualitatively consistent with the experimentally found retention of radiocaesium in the human body after pectin treatment. [ABSTRACT FROM AUTHOR]

Abstract Synaptic cargo trafficking is essential for synapse formation, function and plasticity. In order to transport synaptic cargo, such as synaptic vesicle precursors, mitochondria, neurotransmitter receptors and signaling proteins to their site of action, neurons make use of molecular motor proteins. These motors operate on the microtubule and actin cytoskeleton and are highly regulated so that different cargos can be transported to distinct synaptic specializations at both pre- and post-synaptic sites. How synaptic cargos achieve specificity, directionality and timing of transport is a developing area of investigation. Recent studies demonstrate that the docking of motors to their cargos is a key control point. Moreover, precise spatial and temporal regulation of motor-cargo interactions is important for transport specificity and cargo recruitment. Local signaling pathways Ca2+ influx, CaMKII signaling and Rab GTPase activity regulate motor activity and cargo release at synaptic locations. We discuss here how different motors recognize their synaptic cargo and how motor-cargo interactions are regulated by neuronal activity.

The present guidelines are aimed at residents and board-certified physicians in the fields of dermatology, pediatrics, pediatric dermatology and pediatric rheumatology as well as policymakers and insurance funds. They were developed by dermatologists and pediatric dermatologists in collaboration with pediatric rheumatologists using a formal consensus process (S2k). The guidelines highlight topics such as disease severity, quality of life, treatment goals as well as problems associated with off-label drug therapy in children. Trigger factors and diagnostic aspects are discussed. The primary focus is on the various topical, systemic and UV-based treatment options available and includes recommendations for use and treatment algorithms. Other aspects addressed herein include vaccinations in children and adolescents with psoriasis as well as various disease subtypes such as guttate psoriasis, diaper psoriasis, pustular psoriasis and psoriatic arthritis. Finally, we also provide recommendations for imaging studies and the diagnostic workup to rule out tuberculosis prior to initiating systemic treatment. Note: This article constitutes part 1 of the Sk2 guidelines for the treatment of psoriasis in children and adolescents. Part 2 will be published in the next issue. It contains chapters on UV therapy, systemic treatment, tonsillectomy and antibiotics, vaccinations, guttate psoriasis, psoriatic arthritis, complementary medicine, as well as imaging studies and diagnostic workup to rule out tuberculosis prior to systemic treatment., (© 2019 The Authors | Journal compilation © Blackwell Verlag GmbH, Berlin.)

Three widely used anthropomorphic phantoms are analysed with regard to their suitability for the efficiency calibration of whole-body counters (WBCs): a Bottle Manikin Absorber (BOMAB) phantom consisting of water-filled plastic containers, a St Petersburg block phantom (Research Institute of Sea Transport Hygiene, St Petersburg) made of polyethylene bricks and a mathematical Medical Internal Radiation Dose (MIRD) phantom, each of them representing a person weighing 70 kg. The analysis was performed by means of Monte Carlo simulations with the Monte Carlo N-Particle transport code using detailed mathematical models of the phantoms and the WBC at Forschungszentrum Jülich (FZJ). The simulated peak efficiencies for the BOMAB phantom and the MIRD phantom agree very well, but the results for the St Petersburg phantom are considerably higher. Therefore, WBCs similar to that at FZJ will probably underestimate the activity of incorporated radionuclides if they are calibrated by means of a St Petersburg phantom. Finally, the results from this work are compared with the conclusions from other studies dealing with block and BOMAB phantoms.

After the Chernobyl reactor accident wide areas of Belarus were contaminated with radioactive fallout. The verification and documentation of the long-term development of radiation doses is still going on. A population group of special concern are the children living in contaminated regions. The annual dose limit of 1 mSv is still exceeded in some cases, essentially due to high body burdens of 137Cs as indicated by screening measurements with portable incorporation monitors. In this situation the evaluation of possible dose reduction measures in addition to the control of food contamination is being investigated. Special attention is given to the therapeutic application of a pectin preparation (Vitapect), for which a dose-lowering effect is presumed by Belarusian scientists. In a placebo-controlled double-blind study, several groups of contaminated children received a pectin compound named Vitapect for a two-week period during their stay in a sanatorium. For comparison the same number of control groups were given a placebo preparation. The 137Cs body burden of the children was measured at the beginning and the end. The mean relative reduction of the specific activity within the Vitapect groups was found to be approximately 33%, whereas the specific activity of the children who received a placebo decreased only by approximately 14%, due to clean food supply. It is known that pectins chemically bind cations like caesium in the gastrointestinal tract and thereby increase faecal excretion. Theoretical calculations based on this assumption and considering metabolism processes are qualitatively consistent with the experimentally found retention of radiocaesium in the human body after pectin treatment.

The cytosolic matrix domain (MD) located between amino acids (aa) 103 and 124 of the large hepatitis B virus envelope protein L is essential for virion formation. We reduced the distance between MD and the transmembrane domain (TD; aa 254 to 272) by deletions starting at aa 132. Six mutants with deletions of up to aa 234 were wild type, and four mutants with slightly larger deletions were blocked with respect to virion morphogenesis. Thus, the minimal distance between MD and TD was around 26 aa. This spacer might be required by MD to reach contact sites on the capsid.