82 research outputs found
Association of Inter-individual Differences in Imaging Markers with Schizophrenia Phenotypes
No full textIntroductionNeuroimaging studies have identified several candidate biomarkers of schizophrenia. However, it is unclear whether the considerable variability in these neurobiological correlates between patients can be translated into the clinical setting.ObjectivesWe aimed to identify neuroimaging predictors of clinical course in patients with schizophrenia. Combined with the identification of genetically determined markers of schizophrenia risk, our studies aimed to elucidate the biological basis and the clinical relevance of inter-individual variability between patients.MethodsWe included over 150 patients with schizophrenia and 279 healthy volunteers across five neuroimaging centers in the framework of the IMAGEMEND project [1]. We performed multiple studies on MRI scans using random forests and ROC curves to predict clinical course. Data from healthy controls served to normalize the data from the clinical population and to provide a benchmark for the findings.ResultsWe identified ensembles of neuroimaging markers and of genetic variants predictive of clinical course. Results highlight that (i) brain imaging carries significant clinical information, (ii) clinical information at baseline can considerably increase prediction accuracy.ConclusionThe methodological challenges and the results will be discussed in the context of recent findings from other multi-site studies. We conclude that brain imaging data on their own right are relevant to stratify patients in terms of clinical course; however, complementing these data with other modalities such as genetics and clinical information is necessary to further develop the field towards clinical application of the predictions.Disclosure of interestGiulio Pergola is the academic supervisor of a Hoffmann-La Roche Collaboration grant that partially funds his salary.</jats:sec
La «Historia Ecclesiastica» di Isaac Newton, a cura di G. VESPIGNANI, Bologna, Bononia University Press, 2017 (Studi sul patrimonio culturale. Collana del Dipartimento di Beni Culturali dell’Ateneo di Bologna, 4)
No full textIl volume raccoglie gli interventi presentati ad una delle Giornate italo-spagnole organizzate da Vespignani presso il Dipartimento di Beni Culturali dell'Ateneo di Bologna, sede di Ravenna, quella dedicata alla "Historia Ecclesiastica" scritta da Isaac Newton, allo scopo di valorizzare e diffondere anche in Italia il progetto del Comitato Nazionale per le Ricerche Spagnolo (Madrid), consistente nella traduzione dell'opera dal latino allo spagnolo (prima traduzione in una lingua moderna) e nello studio del testo. La "Historia Ecclesiastica" del newton è interessante in quanto si tratta della storia della Chiesa antica (secoli IV-VI) letta attraverso gli occhiali di un anglicano anti-papalino del Settecento: ne traspaiono i luoghi comuni, la lettura protestante delle vicende della chiesa "romana" e l'uso strumentale che di essa si fece in Inghilterra lungo i secoli
Evocative gene-environment correlation between genetic risk for schizophrenia and bullying victimization
No full textBullying exposure concerns over 10% of adolescents in Europe. Moreover, bullying victimization is heritable and victims are liable to psychotic symptoms, partly because of shared heritability with psychosis. The genetic component of bullying victimization has been proposed to involve the social reactions elicited by victims – a mechanism called “evocative gene-environment correlation”.
We hypothesized that genetic risk for schizophrenia, a heritable disease also associated with social stress during childhood and adolescence, is related with social experiences during adolescence and is involved in the risk of developing psychotic symptoms. We studied 908 individuals of the TRAILS sample and found that 13-14-year-old adolescents with greater genetic risk for schizophrenia are more exposed to bullying assessed via peer nomination scores than their peers with lower genetic risk. Importantly, bullying victimization mediated the path from genetic risk to the frequency of psychotic symptoms about three years later. These findings provide evidence of a previously unreported form of gene-environment interplay that may be a mechanism of risk for psychosis and schizophrenia. To the extent that genetic risk translation into clinical symptoms is mediated by environmental risk factors, this evidence supports mental health prevention aimed at antagonizing bullying victimization in vulnerable individuals
A thalamo-cortical genetic co-expression network is associated with thalamic functional connectivity linked with familial risk for schizophrenia
No full textIntroduction
The genetic architecture of schizophrenia is based on polygenic trajectories. Indeed, genes converge on molecular co-expression pathways, which may be associated with heritable characteristics of patients and their siblings, called intermediate phenotypes, such as prefrontal anomalies and thalamic dysconnectivity during attentional control [2].
Objectives
Here, we investigated in healthy humans association between co-expression of genes with coordinated thalamo-prefrontal (THA-PFC) expression and functional connectivity during attentional control.
Methods
We used Brainspan dataset to characterize a coordinated THA-PFC expression gene list by correlating post-mortem gene expression in both areas (Kendall's Tau>.76, Bonferroni P < .05). Then, we identified a PFC co-expression network1 and tested all gene sets for THA-PFC and PGC loci [3] enrichments (P < .05). SNPs associated with the first principal component of the resulting enriched gene set were combined in a Polygenic Co-Expression Index (PCI) [1]. We conducted Independent Component Analysis (ICA) on attentional control fMRI data (n = 265) and selected Independent Components (ICs) including the thalamus and being highly correlated with an attentional control network2. Multiple regressions were conducted (predictor: PCI) using a thalamic cluster previously associated with familial risk for schizophrenia [2] as ROI (FWE P < .05).
Results
In one of the 8 ICs of interest there was a positive effect of PCI on thalamic connectivity strength in a cluster overlapping with our ROI (Z = 4.3).
Conclusion
Decreased co-expression of genes included in PCI predicts thalamic dysconnectivity during attentional control, suggesting a novel co-regulated molecular pathway potentially implicated in genetic risk for schizophrenia
The transcriptomic context of DRD1 is associated with prefrontal activity and behavior during working memory
No full textDopamine D1 receptor (D1R) signaling shapes prefrontal cortex (PFC) activity during working memory (WM). Previous reports found higher WM performance associated with alleles linked to greater expression of the gene coding for D1Rs (DRD1). However, there is no evidence on the relationship between genetic modulation of DRD1 expression in PFC and patterns of prefrontal activity during WM. Furthermore, pre- vious studies have not considered that D1Rs are part of a coregulated molecular environment, which may contribute to D1R-related prefron- tal WM processing. Thus, we hypothesized a reciprocal link between a coregulated (i.e., coexpressed) molecular network including DRD1 and PFC activity. To explore this relationship, we used three indepen- dent postmortem prefrontal mRNA datasets (total n = 404) to char- acterize a coexpression network including DRD1. Then, we indexed network coexpression using a measure (polygenic coexpression index—DRD1-PCI) combining the effect of single nucleotide polymor- phisms (SNPs) on coexpression. Finally, we associated the DRD1-PCI with WM performance and related brain activity in independent sam- ples of healthy participants (total n = 371). We identified and repli- cated a coexpression network including DRD1, whose coexpression was correlated with DRD1-PCI. We also found that DRD1-PCI was associated with lower PFC activity and higher WM performance. Be- havioral and imaging results were replicated in independent samples. These findings suggest that genetically predicted expression of DRD1 and of its coexpression partners stratifies healthy individuals in terms of WM performance and related prefrontal activity. They also high- light genes and SNPs potentially relevant to pharmacological trials aimed to test cognitive enhancers modulating DRD1 signaling
Thermal neutron detection based on resistive gaseous devices
No full textIn the uRANIA-V project, new gaseous detector technologies for neutron detection were explored. The first is the micro-Resistive WELL (mu -RWELL), mu- RWELL), a compact resistive MPGD with a single amplification stage. The second is the surface-Resistive Plate Counter (sRPC), a new generation RPC based on surface resistivity. Both detectors used 10 B 4 C converters to detect thermal neutrons, achieving efficiencies of 5-10 %
uRANIA: μ-RWELL and sRPC for neutron detection
No full textThe goal of the uRANIA-V (μ-RWELL Advanced Neutron Imaging Apparatus) project is the development of an innovative thermal neutron detector based on micro-Resistive WELL (μ-RWELL) technology and surface Resistive Plate Counter (sRPC) technology. A thin layer of 10B4C on the cathode surface allows the thermal neutron conversion into 7Li and α ions to be easily detected in the active volume of the device. These charged particles ionize the gas in the detectors and the readout measures the signal. Test results with different converter layouts show that a thermal neutron (25meV) detection efficiency between 5 ÷ 10 % can be achieved with a single detector. A detailed comparison between the experimental data and the full simulation of the neutron physics and the detector behavior has been performed. Future applications of these technologies range from neutron diffraction imaging to radioactive waste monitor or radiation portal monitoring for homeland security. In this proceeding, the results of the neutron conversion optimization of the Boron thickness and the converted geometry will be discussed together with the development of new electronics integrated with μ-RWELL and sRPC. Experimental results and simulation measurements will be compared
uRANIA: A micro-Resistive WELL for neutron detection
No full textThe goal of the uRANIA-V (μ-RWELL Advanced Neutron Imaging Apparatus) project is the development of an innovative thermal neutron detector based on μ-RWELL technology. The μ-RWELL is a reliable, cost effective, easily scalable, resistive MPGD. A thin layer of 10B4C on the cathode surface allows the thermal neutron conversion into products easily detected by the device. Results, performed with different converter layouts, show a thermal neutron (25meV) detection efficiency between 3 and 10
Thermal neutron detection based on resistive gaseous devices
No full textIn the uRANIA-V project, new gaseous detector technologies for neutron detection were explored. The first is the micro-Resistive WELL (μ-RWELL), a compact resistive MPGD with a single amplification stage. The second is the surface-Resistive Plate Counter (sRPC), a new generation RPC based on surface resistivity. Both detectors used 10B4C converters to detect thermal neutrons, achieving efficiencies of 5–10%
Direct detection of minimum ionizing charged particles in a perovskite single crystal detector with single particle sensitivity
No full textWe report the detection of high energy electrons of some hundreds of MeV, crossing a methylammonium lead bromide single crystal device with sensitivity down to a single electron. In the device, the released energy is close to the energy released by minimum-ionizing particles. This is the first demonstration of a perovskite-based device that can be used for tracking and counting minimum-ionizing charged particles. The device reaches single particle sensitivity with a low bias voltage of 5 V. It also shows a good linearity of the response as a function of the number of electrons in a dynamic range of approximately 104.First demonstration of a perovskite-based device that can be used for tracking and counting minimum-ionizing charged particles. Sensitivity down to a single particle (300 MeV electron) crossing a methylammonium lead bromide crystal has been obtained
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