Pilot performance of a dedicated prostate PET suitable for diagnosis and biopsy guidance

[EN] Background: Prostate cancer (PCa) represents one of the most common types of cancers facing the male population. Nowadays, to confirm PCa, systematic or multiparametric MRI-targeted transrectal or transperineal biopsies of the prostate are required. However, due to the lack of an accurate imaging technique capable to precisely locate cancerous cells in the prostate, ultrasound biopsies sample random parts of the prostate and, therefore, it is possible to miss regions where those cancerous cells are present. In spite of the improvement with multiparametric MRI, the low reproducibility of its reading undermines the specificity of the method. Recent development of prostatespecific radiotracers has grown the interest on using positron emission tomography (PET) scanners for this purpose, but technological improvements are still required (current scanners have resolutions in the range of 4¿5 mm). Results: The main goal of this work is to improve state-of-the-art PCa imaging and diagnosis. We have focused our efforts on the design of a novel prostate-dedicated PET scanner, named ProsPET. This system has small scanner dimensions defined by a ring of just 41 cm inner diameter. In this work, we report the design, implementation, and evaluation (both through simulations and real data) of the ProsPET scanner. We have been able to achieve < 2 mm resolution in reconstructed images and high sensitivity. In addition, we have included a comparison with the Philips Gemini-TF scanner, which is used for routine imaging of PCa patients. The ProsPET exhibits better contrast, especially for rod sizes as small as 4.5 mm in diameter. Finally, we also show the first reconstructed image of a PCa patient acquired with the ProsPET. Conclusions: We have designed and built a prostate specific PET system, with a small footprint and improved spatial resolution when compared to conventional whole-body PET scanners. The gamma ray impact within each detector block includes accurate DOI determination, correcting for the parallax error. The potential role of combined organdedicated prostate-specific membrane antigen (PSMA) PET and ultrasound devices, as a prebiopsy diagnostic tool, could be used to guide sampling of the most aggressive sites in the prostate.The work presented in this article has been partially funded by a research grant from the regional government of the Comunitat Valenciana (Spain), co-funded by the European Union ERDF funds (European Regional Development Fund) of the Comunitat Valenciana 2014-2020, with reference IDIFEDER/2018/032 (High-Performance Algorithms for the Modelling, Simulation and early Detection of diseases in Personalized Medicine). This project has also received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program (grant agreement No 695536). It has also been supported by the EU Grant 603002 under the FP7 program and by the Spanish Ministerio de Economia, Industria y Competitividad under Grant e and through PROSPET (DTS15/00152) funded by the Ministerio de Economia y Competitividad.Cañizares-Ledo, G.; Gonzalez-Montoro, A.; Freire, M.; Lamprou, E.; Barrio, J.; Sánchez Martínez, F.; Benlloch Baviera, JM.... (2020). Pilot performance of a dedicated prostate PET suitable for diagnosis and biopsy guidance. EJNMMI Physics. 7(1):1-17. https://doi.org/10.1186/s40658-020-00305-yS11771GLOBOCAN 2018. http://www.gco.iarc.fr/today/ datasources-methods. Accessed 26 Dec 2019.Ferlay J, et al. Cancer incidence and mortality worldwide: sources, methods and major patterns in GLOBOCAN. Int J Cancer. 2012;2015:136–E359.Rawla P. Epidemiology of prostate cancer. 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Essential¿but also vulnerable? Work intensification, effort/reward imbalance, fatigue and psychological health of Spanish cargo drivers during the COVID-19 pandemic

Objective: This study investigates the combined effect of the Effort/Reward Imbalance (ERI) model of stress and work intensification within the context of the COVID-19 pandemic on the psychological health (general and work-related fatigue, and psychological strain) of cargo drivers, one of the most demanded workforces during the first year of this pandemic. Methods: For this cross-sectional research, the data provided by n = 1,013 professional drivers from the different 17 autonomous communities (regions) of Spain were analyzed. Participants answered a questionnaire composed of the short version of the Effort Reward Imbalance (ERI) questionnaire, a Work Intensification Scale (WIS) designed for this study, the fatigue subscale of the Checklist Individual Strength (CIS), the Need for Recovery after Work Scale (NFR), and the General Health Questionnaire (GHQ). Results: Hierarchical regression analyses show that both (ERI and work intensification) models significantly predict driver's fatigue and psychological strain. The effect of work intensification exists above and beyond the effect of effort/reward imbalance, which has been previously related to the safety performance of cargo drivers. Conclusions: These findings suggest that the ERI and work intensification models can be complementarily used, especially in scenarios introducing substantial changes in the work environment, such as the COVID-19 crisis. Also, the results of this study support the need to intervene in the working conditions of professional drivers in order to improve their psychological health and well-being during both pandemic and post-pandemic times, as crisis-related management interventions are necessar

Improving EEG-Based Motor Imagery Classification for Real-Time Applications Using the QSA Method

We present an improvement to the quaternion-based signal analysis (QSA) technique to extract electroencephalography (EEG) signal features with a view to developing real-time applications, particularly in motor imagery (IM) cognitive processes. The proposed methodology (iQSA, improved QSA) extracts features such as the average, variance, homogeneity, and contrast of EEG signals related to motor imagery in a more efficient manner (i.e., by reducing the number of samples needed to classify the signal and improving the classification percentage) compared to the original QSA technique. Specifically, we can sample the signal in variable time periods (from 0.5 s to 3 s, in half-a-second intervals) to determine the relationship between the number of samples and their effectiveness in classifying signals. In addition, to strengthen the classification process a number of boosting-technique-based decision trees were implemented. The results show an 82.30% accuracy rate for 0.5 s samples and 73.16% for 3 s samples. This is a significant improvement compared to the original QSA technique that offered results from 33.31% to 40.82% without sampling window and from 33.44% to 41.07% with sampling window, respectively. We can thus conclude that iQSA is better suited to develop real-time applications

Current status of the 12 MeV UPC race-track microtron

A com­pact race-track mi­crotron (RTM) with the max­i­mal out­put en­er­gy 12 MeV is under con­struc­tion at the Uni­ver­si­tat Politècnica de Catalun­ya (UPC) in col­lab­o­ra­tion with the Sko­belt­syn In­sti­tute of Nu­cle­ar Physics of the Moscow State Uni­ver­si­ty, CIEMAT and a few Span­ish in­dus­tri­al com­pa­nies and med­i­cal cen­ters. The RTM end mag­nets are four-pole sys­tems with the mag­net­ic field cre­at­ed by a rare-earth per­ma­nent mag­net ma­te­ri­al. As a source of elec­trons a 3D off-ax­is elec­tron gun is used. These el­e­ments to­geth­er with a C-band ac­cel­er­at­ing struc­ture, dipole mag­nets, which allow to ex­tract the elec­tron beam with en­er­gy from 6 MeV to 12 MeV in 2 MeV step, and a fo­cus­ing quadrupole are placed in­side a vac­u­um cham­ber. We re­port on the cur­rent sta­tus of the tech­ni­cal de­sign and re­sults of tests of some of the com­po­nents.Postprint (published version

Specificity of Transmembrane Protein Palmitoylation in Yeast

Many proteins are modified after their synthesis, by the addition of a lipid molecule to one or more cysteine residues, through a thioester bond. This modification is called S-acylation, and more commonly palmitoylation. This reaction is carried out by a family of enzymes, called palmitoyltransferases (PATs), characterized by the presence of a conserved 50- aminoacids domain called “Asp-His-His-Cys- Cysteine Rich Domain” (DHHC-CRD). There are 7 members of this family in the yeast Saccharomyces cerevisiae, and each of these proteins is thought to be responsible for the palmitoylation of a subset of substrates. Substrate specificity of PATs, however, is not yet fully understood. Several yeast PATs seem to have overlapping specificity, and it has been proposed that the machinery responsible for palmitoylating peripheral membrane proteins in mammalian cells, lacks specificity altogether

Cross-culturally approaching the cycling behaviour questionnaire (CBQ) : Evidence from 19 countries

Peer reviewe

A survey for variable young stars with small telescopes: II - mapping a protoplanetary disc with stable structures at 0.15 au

The HOYS citizen science project conducts long term, multifilter, high cadence monitoring of large YSO samples with a wide variety of professional and amateur telescopes. We present the analysis of the light curve of V1490 Cyg in the Pelican Nebula. We show that colour terms in the diverse photometric data can be calibrated out to achieve a median photometric accuracy of 0.02 mag in broadband filters, allowing detailed investigations into a variety of variability amplitudes over timescales from hours to several years. Using Gaia DR2 we estimate the distance to the Pelican Nebula to be 870 +70 −55 pc. V1490 Cyg is a quasi-periodic dipper with a period of 31.447 ± 0.011 d. The obscuring dust has homogeneous properties, and grains larger than those typical in the ISM. Larger variability on short timescales is observed in U and Rc−Hα, with U-amplitudes reaching 3 mag on timescales of hours, indicating the source is accreting. The Hα equivalent width and NIR/MIR colours place V1490 Cyg between CTTS/WTTS and transition disk objects. The material responsible for the dipping is located in a warped inner disk, about 0.15 AU from the star. This mass reservoir can be filled and emptied on time scales shorter than the period at a rate of up to 10−10 M�/yr, consistent with low levels of accretion in other T Tauri stars. Most likely the warp at this separation from the star is induced by a protoplanet in the inner accretion disk. However, we cannot fully rule out the possibility of an AA Tau-like warp, or occultations by the Hill sphere around a forming planet

Genomic and phenotypic insights from an atlas of genetic effects on DNA methylation

DNA methylation quantitative trait locus (mQTL) analyses on 32,851 participants identify genetic variants associated with DNA methylation at 420,509 sites in blood, resulting in a database of >270,000 independent mQTLs.Characterizing genetic influences on DNA methylation (DNAm) provides an opportunity to understand mechanisms underpinning gene regulation and disease. In the present study, we describe results of DNAm quantitative trait locus (mQTL) analyses on 32,851 participants, identifying genetic variants associated with DNAm at 420,509 DNAm sites in blood. We present a database of >270,000 independent mQTLs, of which 8.5% comprise long-range (trans) associations. Identified mQTL associations explain 15-17% of the additive genetic variance of DNAm. We show that the genetic architecture of DNAm levels is highly polygenic. Using shared genetic control between distal DNAm sites, we constructed networks, identifying 405 discrete genomic communities enriched for genomic annotations and complex traits. Shared genetic variants are associated with both DNAm levels and complex diseases, but only in a minority of cases do these associations reflect causal relationships from DNAm to trait or vice versa, indicating a more complex genotype-phenotype map than previously anticipated.Molecular Epidemiolog