Structure and properties of DOTA-chelated radiopharmaceuticals within the 225Ac decay pathway

The successful delivery of toxic cargo directly to tumor cells is of primary importance in targeted (α) particle therapy. Complexes of radioactive atoms with the 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelating agent are considered as effective materials for such delivery processes. The DOTA chelator displays high affinity to radioactive metal isotopes and retains this capability after conjugation to tumor targeting moieties. Although the α-decay chains are well defined for many isotopes, the stability of chelations during the decay process and the impact of released energy on their structures remain unknown. The radioactive isotope 225Ac is an α-particle emitter that can be easily chelated by DOTA. However, 225Ac has a complex decay chain with four α-particle emissions during decay of each radionuclide. To advance our fundamental understanding of the consequences of α-decay on the stability of tumor-targeted 225Ac–DOTA conjugate radiopharmaceuticals, we performed first principles calculations of the structure, stability, and electronic properties of the DOTA chelator to the 225Ac radioactive isotope, and the initial daughters in the decay chain, 225Ac, 221Fr, 217At and 213Bi. Our calculations show that the atomic positions, binding energies, and electron localization functions are affected by the interplay between spin–orbit coupling, weak dispersive interactions, and environmental factors. Future empirical measurements may be guided and interpreted in light of these results

Social media in democratic transitions and consolidations: what can we learn from the case of Tunisia?

© 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group. The aim of this paper is to analyse the use of social media in the stages of uprising, democratic transition and democratic consolidation using the case study of Tunisia. While the impact of social media in uprisings has been widely documented in past research about the MENA region, Tunisia provides new evidence to the use of Internet in the processes of democratisation. Consequently, this research focuses in detail on the benefits but also the pitfalls of social media in transitions and consolidations. Data collection was based on interviews with Tunisian social media activists. The analysis is valuable to social media practitioners and researchers alike

A collaborative approach to exploring the future of Cancer treatment and care in relation to Precision Medicine: A design perspective.

The Precision Medicine and the Future of Cancer project was jointly conceived by the Innovation School at Glasgow School of Art and the Institute of Cancer Sciences at the University of Glasgow. Graduating year Product Design students from the Innovation School were presented with a challenge-based project to produce a vision of the future based on current trends that relate to Precision Medicine(PM) and Cancer treatment. This project involved working closely with scientists, clinicians, patients, industry and academic professionals from Glasgow University, staff at Queen Elizabeth University Hospital and Clinical Innovation Zone, staff at Beatson West of Scotland Cancer Centre, Patient Representatives and external design experts from Studio AndThen and GOODD design consultancy. The objective of this project was to investigate, in both analytical and speculative ways, future forms and functions of cancer treatment and care in relation to Precision Medicine, to develop future scenarios and design artefacts, services, and the experiences associated with them. One of the most significant societal shifts currently taking place within the field of PM is the transformation around what it means to be a patient and a professional working within this context. The public’s role is developing beyond once-passive patients into stakeholders valued within the medical industry and healthcare sector for their participation in clinical trials, and contribution towards policy-making and decision-making committees. This new dynamic is changing the traditional patient-doctor relationship and challenging the hegemony of medical practice at an institutional level. The impetus for this shift is relentless technological acceleration and increased scientific research, in particular driven by advances in PM. This project asked students to consider what will happen in a cancer landscape ten years from now, where PM has evolved to the extent that new forms of medical practice, cancer treatment and care transform how we interact with each other, with professionals and the world around us. The brief gave students the opportunity to reflect on the underlying complexities regarding the future of health, technological acceleration, post-capitalism and human agency, to envision a future world context, develop it as an experiential exhibit, and produce the designed products, services and experiences for the people who might live and work within it. The project was divided into two sections: The first was a collaborative stage where groups of students were assigned a specific area of focus from Social, Technological, Economic, Ethical, Educational, Political, Legal, Ecological [STEEEPLE]. These groups focused on researching and exploring their specific lenses and gathering as much information and understanding while working with external experts to further their knowledge. This group stage culminated in an exhibition of the collaborative understanding of what the future could look like in 10 years from now, after exploring the possible consequences of current actions. The second stage saw students explore their individual response to the world that had been defined in the first stage. Each student had their own response to the research by iteratively creating a design outcome that was appropriate to the subject matter. This culminated in each student having created a design product/service/experience relating to the future scenario. A full report (Project Process Journal [PPJ]) is included within the repository of each student which breaks down their process of designing and the outcome they have designed. The project aims to tackle the emerging possibilities where medical professionals and design can collaborate, to create a future where forms of medical practice are more preventative and are more appropriate for an aging population now and into the future. The deposited materials are arranged as follows: Readme files - two readme files relate to stage one and stage two of the project as outlined above. Overview poster - gives a visual overview of the structure and timeline of the project. Data folders - the data folders for stage one of the project are named for the lens through which each group viewed possible futures. The data folders for stage two of the project are named for the individual students who conducted the work

Structure and Properties of DOTA-chelated Radiopharmaceuticals Within the 225Ac Decay Pathway

The successful delivery of toxic cargo directly to tumor cells is of primary importance in targeted (α) particle therapy. Complexes of radioactive atoms with the 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) chelating agent are considered as effective materials for such delivery processes. The DOTA chelator displays high affinity to radioactive metal isotopes and retains this capability after conjugation to tumor targeting moieties. Although the α-decay chains are well defined for many isotopes, the stability of chelations during the decay process and the impact of released energy on their structures remain unknown. The radioactive isotope 225Ac is an α-particle emitter that can be easily chelated by DOTA. However, 225Ac has a complex decay chain with four α-particle emissions during decay of each radionuclide. To advance our fundamental understanding of the consequences of α-decay on the stability of tumor-targeted 225Ac–DOTA conjugate radiopharmaceuticals, we performed first principles calculations of the structure, stability, and electronic properties of the DOTA chelator to the 225Ac radioactive isotope, and the initial daughters in the decay chain, 225Ac, 221Fr, 217At and 213Bi. Our calculations show that the atomic positions, binding energies, and electron localization functions are affected by the interplay between spin–orbit coupling, weak dispersive interactions, and environmental factors. Future empirical measurements may be guided and interpreted in light of these results

Complex Compound Inheritance of Lethal Lung Developmental Disorders Due to Disruption of the TBX-FGF Pathway

International audiencePrimary defects in lung branching morphogenesis, resulting in neonatal lethal pulmonary hypoplasias, are incompletely understood. To elucidate the pathogenetics of human lung development, we studied a unique collection of samples obtained from deceased individuals with clinically and histopathologically diagnosed interstitial neonatal lung disorders: acinar dysplasia (n = 14), congenital alveolar dysplasia (n = 2), and other lethal lung hypoplasias (n = 10). We identified rare heterozygous copy-number variant deletions or single-nucleotide variants (SNVs) involving TBX4 (n = 8 and n = 2, respectively) or FGF10 (n = 2 and n = 2, respectively) in 16/26 (61%) individuals. In addition to TBX4, the overlapping similar to 2 Mb recurrent and nonrecurrent deletions at 17q23.1q23.2 identified in seven individuals with lung hypoplasia also remove a lung-specific enhancer region. Individuals with coding variants involving either TBX4 or FGF10 also harbored at least one non-coding SNV in the predicted lung-specific enhancer region, which was absent in 13 control individuals with the overlapping deletions but without any structural lung anomalies. The occurrence of rare coding variants involving TBX4 or FGF10 with the putative hypomorphic non-coding SNVs implies a complex compound inheritance of these pulmonary hypoplasias. Moreover, they support the importance of TBX4-FGF10-FGFR2 epithelial-mesenchymal signaling in human lung organogenesis and help to explain the histopathological continuum observed in these rare lethal developmental disorders of the lung

Reproducibility of CRISPR-Cas9 methods for generation of conditional mouse alleles: a multi-center evaluation

BackgroundCRISPR-Cas9 gene-editing technology has facilitated the generation of knockout mice, providing an alternative to cumbersome and time-consuming traditional embryonic stem cell-based methods. An earlier study reported up to 16% efficiency in generating conditional knockout (cKO or floxed) alleles by microinjection of 2 single guide RNAs (sgRNA) and 2 single-stranded oligonucleotides as donors (referred herein as “two-donor floxing” method).ResultsWe re-evaluate the two-donor method from a consortium of 20 laboratories across the world. The dataset constitutes 56 genetic loci, 17,887 zygotes, and 1718 live-born mice, of which only 15 (0.87%) mice contain cKO alleles. We subject the dataset to statistical analyses and a machine learning algorithm, which reveals that none of the factors analyzed was predictive for the success of this method. We test some of the newer methods that use one-donor DNA on 18 loci for which the two-donor approach failed to produce cKO alleles. We find that the one-donor methods are 10- to 20-fold more efficient than the two-donor approach.ConclusionWe propose that the two-donor method lacks efficiency because it relies on two simultaneous recombination events in cis, an outcome that is dwarfed by pervasive accompanying undesired editing events. The methods that use one-donor DNA are fairly efficient as they rely on only one recombination event, and the probability of correct insertion of the donor cassette without unanticipated mutational events is much higher. Therefore, one-donor methods offer higher efficiencies for the routine generation of cKO animal models