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Optimization of screening for radioactivity in urine by liquid scintillation.
Numerous events have or could have resulted in the inadvertent uptake of radionuclides by fairly large populations. Should a population receive an uptake, valuable information could be obtained by using liquid scintillation counting (LSC) techniques to quickly screen urine from a sample of the affected population. This study investigates such LSC parameters as discrimination, quench, volume, and count time to yield guidelines for analyzing urine in an emergency situation. Through analyzing variations of the volume and their relationships to the minimum detectable activity (MDA), the optimum ratio of sample size to scintillating chemical cocktail was found to be 1:3. Using this optimum volume size, the alpha MDA varied from 2100 pCi/L for a 30-second count time to 35 pCi/L for a 1000-minute count time. The typical count time used by the Sandia National Laboratories Radiation Protection Sample Diagnostics program is 30 minutes, which yields an alpha MDA of 200 pCi/L. Because MDA is inversely proportional to the square root of the count time, count time can be reduced in an emergency situation to achieve the desired MDA or response time. Note that approximately 25% of the response time is used to prepare the samples and complete the associated paperwork. It was also found that if the nuclide of interest is an unknown, pregenerated discriminator settings and efficiency calibrations can be used to produce an activity value within a factor of two, which is acceptable for a screening method
Dielectronic satellite emission from a solid-density Mg plasma: Relationship to models of ionization potential depression
Producción CientíficaWe report on experiments where solid-density Mg plasmas are created by heating with the focused output of the Linac Coherent Light Source x-ray free-electron laser. We study the K-shell emission from the helium and lithium-like ions using Bragg crystal spectroscopy. Observation of the dielectronic satellites in lithium-like ions confirms that the M-shell electrons appear bound for these high charge states. An analysis of the intensity of these satellites indicates that when modeled with an atomic-kinetics code, the ionization potential depression model employed needs to produce depressions for these ions which lie between those predicted by the well known Stewart-Pyatt and Ecker-Kroll models. These results are largely consistent with recent density functional theory calculations.This work has received support from the Spanish Ministry of Science and Innovation under Research Grants No. PID2019-108764RB-I00 and No. PID2022-137632OB-I00
Golimumab induction and maintenance for moderate to severe ulcerative colitis: results from GO-COLITIS (Golimumab: a Phase 4, UK, open label, single arm study on its utilization and impact in ulcerative Colitis)
Objective GO-COLITIS aimed to measure the effectiveness of subcutaneous golimumab in tumour necrosis factor-α antagonist–naive patients with moderate to severe ulcerative colitis (UC) despite conventional treatment.
Design GO-COLITIS was an open label, single arm, phase 4 study with a pragmatic design which reflected UK clinical practice. Adult patients were eligible if diagnosed with UC ≥3 months, partial Mayo score (PMS) 4–9. Patients received subcutaneous golimumab induction (200 mg initially and 100 mg at week 2) followed at week 6 by 50 mg or 100 mg (depending on weight) every 4 weeks until week 54 with a 12-week follow-up. Efficacy was measured by PMS at baseline, week 6, 30, 54 and 66. Health-related quality of life (HRQoL; Inflammatory Bowel Disease Questionnaire (IBDQ) and EuroQol Group 5 Dimensions Health Questionnaire (EQ-5D)) was assessed at baseline, week 6 and week 54. All safety adverse events (AEs) were recorded.
Results 207 patients were enrolled and 205 received golimumab (full analysis set (FAS)205). At week 6, 68.8% (95% CI 62.0% to 75.1%) and 38.5% (95% CI 31.8% to 45.6%) of patients were in response and remission, respectively, using PMS. At the end of the induction phase, 140/141 patients in clinical response continued into the maintenance phase (Maintenance FAS). Sustained clinical response through week 54 was achieved in 51/205 (24.9%) of the FAS205 population and 51/140 (36.4%) of the Maintenance FAS population. Statistically significant improvements from baseline to week 6 were observed for the IBDQ total score and for each IBDQ domain score (bowel symptoms, emotional function, systemic symptoms and social function), as well as the EQ-5D index score and associated visual analogue scale score (p<0.0001). Improvement of HRQoL was sustained through week 54. Serious AEs leading to treatment discontinuation occurred in 8.8% of patients.
Conclusion In this study measuring patient-reported outcomes in patients with moderate to severe UC, golimumab induced and maintained response as measured by PMS and significantly improved quality of life measures.
Trial registration number NCT02092285; 2013-004583-56
Natural history of Arabidopsis thaliana and oomycete symbioses
Molecular ecology of plant–microbe interactions has immediate significance for filling a gap in knowledge between the laboratory discipline of molecular biology and the largely theoretical discipline of evolutionary ecology. Somewhere in between lies conservation biology, aimed at protection of habitats and the diversity of species housed within them. A seemingly insignificant wildflower called Arabidopsis thaliana has an important contribution to make in this endeavour. It has already transformed botanical research with deepening understanding of molecular processes within the species and across the Plant Kingdom; and has begun to revolutionize plant breeding by providing an invaluable catalogue of gene sequences that can be used to design the most precise molecular markers attainable for marker-assisted selection of valued traits. This review describes how A. thaliana and two of its natural biotrophic parasites could be seminal as a model for exploring the biogeography and molecular ecology of plant–microbe interactions, and specifically, for testing hypotheses proposed from the geographic mosaic theory of co-evolution
Adenosine A2A receptors in Parkinson’s disease treatment
Latest results on the action of adenosine A2A receptor antagonists indicate their potential therapeutic usefulness in the treatment of Parkinson’s disease. Basal ganglia possess high levels of adenosine A2A receptors, mainly on the external surfaces of neurons located at the indirect tracts between the striatum, globus pallidus, and substantia nigra. Experiments with animal models of Parkinson’s disease indicate that adenosine A2A receptors are strongly involved in the regulation of the central nervous system. Co-localization of adenosine A2A and dopaminergic D2 receptors in striatum creates a milieu for antagonistic interaction between adenosine and dopamine. The experimental data prove that the best improvement of mobility in patients with Parkinson’s disease could be achieved with simultaneous activation of dopaminergic D2 receptors and inhibition of adenosine A2A receptors. In animal models of Parkinson’s disease, the use of selective antagonists of adenosine A2A receptors, such as istradefylline, led to the reversibility of movement dysfunction. These compounds might improve mobility during both monotherapy and co-administration with L-DOPA and dopamine receptor agonists. The use of adenosine A2A receptor antagonists in combination therapy enables the reduction of the L-DOPA doses, as well as a reduction of side effects. In combination therapy, the adenosine A2A receptor antagonists might be used in both moderate and advanced stages of Parkinson’s disease. The long-lasting administration of adenosine A2A receptor antagonists does not decrease the patient response and does not cause side effects typical of L-DOPA therapy. It was demonstrated in various animal models that inhibition of adenosine A2A receptors not only decreases the movement disturbance, but also reveals a neuroprotective activity, which might impede or stop the progression of the disease. Recently, clinical trials were completed on the use of istradefylline (KW-6002), an inhibitor of adenosine A2A receptors, as an anti-Parkinson drug
Mapping human dispersals into the Horn of Africa from Arabian Ice Age refugia using mitogenomes
Rare mitochondrial lineages with relict distributions can sometimes be disproportionately informative about deep events in human prehistory. We have studied one such lineage, haplogroup R0a, which uniquely is most frequent in Arabia and the Horn of Africa, but is distributed much more widely, from Europe to India. We conclude that: (1) the lineage ancestral to R0a is more ancient than previously thought, with a relict distribution across the Mediterranean/Southwest Asia; (2) R0a has a much deeper presence in Arabia than previously thought, highlighting the role of at least one Pleistocene glacial refugium, perhaps on the Red Sea plains; (3) the main episode of dispersal into Eastern Africa, at least concerning maternal lineages, was at the end of the Late Glacial, due to major expansions from one or more refugia in Arabia; (4) there was likely a minor Late Glacial/early postglacial dispersal from Arabia through the Levant and into Europe, possibly alongside other lineages from a Levantine refugium; and (5) the presence of R0a in Southwest Arabia in the Holocene at the nexus of a trading network that developed after ~3 ka between Africa and the Indian Ocean led to some gene flow even further afield, into Iran, Pakistan and India
Development of a candidate reference material for adventitious virus detection in vaccine and biologicals manufacturing by deep sequencing.
Unbiased deep sequencing offers the potential for improved adventitious virus screening in vaccines and biotherapeutics. Successful implementation of such assays will require appropriate control materials to confirm assay performance and sensitivity.
A common reference material containing 25 target viruses was produced and 16 laboratories were invited to process it using their preferred adventitious virus detection assay.
Fifteen laboratories returned results, obtained using a wide range of wet-lab and informatics methods. Six of 25 target viruses were detected by all laboratories, with the remaining viruses detected by 4-14 laboratories. Six non-target viruses were detected by three or more laboratories.
The study demonstrated that a wide range of methods are currently used for adventitious virus detection screening in biological products by deep sequencing and that they can yield significantly different results. This underscores the need for common reference materials to ensure satisfactory assay performance and enable comparisons between laboratories
Is there a subjective well-being premium in voluntary sector employment?
Previous studies have found that employment in the voluntary sector offers a so-called ‘job satisfaction premium’: despite lower salaries, voluntary sector employees are more satisfied with their jobs than workers in other sectors. This paper examines whether voluntary sector employees also experience a subjective well-being premium. Using data from the UK Annual Population Survey 2012/2013, we find that voluntary sector employees do have higher levels of subjective well-being but this subjective well-being premium is not evenly distributed between men and women. Men score higher on happiness and life satisfaction. However, women in the voluntary sector have lower levels of life satisfaction compared with their counterparts in the public sector. We discuss the implications of our findings for policy and practice in the voluntary sector in the UK
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