881 resultados para Graph spectrum
Resumo:
Optical coherence tomography (OCT) is a well-established image modality in ophthalmology and used daily in the clinic. Automatic evaluation of such datasets requires an accurate segmentation of the retinal cell layers. However, due to the naturally low signal to noise ratio and the resulting bad image quality, this task remains challenging. We propose an automatic graph-based multi-surface segmentation algorithm that internally uses soft constraints to add prior information from a learned model. This improves the accuracy of the segmentation and increase the robustness to noise. Furthermore, we show that the graph size can be greatly reduced by applying a smart segmentation scheme. This allows the segmentation to be computed in seconds instead of minutes, without deteriorating the segmentation accuracy, making it ideal for a clinical setup. An extensive evaluation on 20 OCT datasets of healthy eyes was performed and showed a mean unsigned segmentation error of 3.05 ±0.54 μm over all datasets when compared to the average observer, which is lower than the inter-observer variability. Similar performance was measured for the task of drusen segmentation, demonstrating the usefulness of using soft constraints as a tool to deal with pathologies.
Resumo:
Purpose of review: We aimed to review literature on the efficacy and tolerability of psychosocial and psychopharmacological interventions in youth with early-onset schizophrenia spectrum disorders (EOS). A rationale for pragmatic psychopharmacology in EOS, including dosing, switching and adverse effect monitoring and management, is provided. Recent findings: Three randomized controlled trials (RCTs) over the last 8 years demonstrated benefits of psychosocial interventions (i.e. psychoeducation, cognitive remediation, cognitive behavioural therapy) for EOS without clear advantages of one psychosocial treatment over another. Six large, placebo-controlled, short-term RCTs over the last 4 years demonstrated that aripiprazole, olanzapine, paliperidone, quetiapine and risperidone, but not ziprasidone, were superior to placebo. Except for clozapine's superiority in treatment-refractory EOS, efficacy appeared similar across studied first-generation and second-generation antipsychotics, but tolerability varied greatly across individual agents. Summary: Antipsychotics are efficacious in the treatment of EOS. Given the lack of efficacy differences between antipsychotics (except for clozapine for treatment-refractory EOS), we propose that tolerability considerations need to guide choice of antipsychotics. Further and longer-term efficacy and effectiveness studies are urgently needed that should also explore pharmacologic and nonpharmacologic augmentation strategies.
Resumo:
Following encouraging results in the early detection of psychotic disorders, interest in the early detection of affective, especially bipolar disorders, has recently been renewed. However, the differentiation between affective disorders with and without psychotic features is often missing, although it has been suggested that affective disorders with psychotic features may be distinct from those without psychotic features and closely linked to non-affective psychoses.
Resumo:
Depressive symptoms in 'non-affective' first episode schizophrenia spectrum disorders (FES) are common, but poorly understood, resulting in a range of conceptual and clinical management issues. This study had three aims: (i) to determine the prevalence of moderate to severe depressive symptoms (defined as a Clinical Global Impressions Scale-Bipolar Disorder (CGI-BP depression) score >3) in a large representative sample of FES patients; (ii) to compare the clinical and functional characteristics of FES patients with and without these depressive symptoms at service entry; and (iii) to compare the characteristics of FES patients with and without persistent depressive symptoms.
Resumo:
Active participation is as essential a skill to children with autism as it is for children without autism, as children are expected to engage in these skills both in and outside the classroom. Without participation skills, children are at a disadvantage when it comes to school and other settings, such as extracurricular activities and the workforce. Recent research has shown that there are interventions available that aim to improve the social skills of children in the home and in the school. These interventions can be delivered in varying forms with the primary caregiver as the interventionist, the specialist as the interventionist, and naturalistic interventions. The purpose of this study was to investigate one of the naturalistic interventions, the Competent Learner Model, and determine its effects on the participation and social skills of students with autism. Three middle school male students diagnosed with autism from a rural northeast middle school participated in the study. They were assessed using the Competent Learner Repertoire Assessments of the Competent Learner Model and the adaptive measures of the Vineland-II and ABAS-II. The results showed improvement for one of the three students and little to no improvement for the other two students.
Resumo:
Autism spectrum disorders (ASD) are pervasive developmental disorders that affect approximately 1 in 50 children (Blumberg et al., 2013). Due to the social nature of the deficits that characterize the disorders, many have classified them as disorders of social cognition, which is the process that individuals use in order to successfully interact with members of their own species (Frith & Frith, 2007). Previous research has typically neglected the spectrum nature of ASD in favor of a more categorical approach of ¿autistic¿ versus ¿non-autistic,¿ but the spectrum requires a more continuous approach. Thus, the present study sought to examine the genetic, social-cognitive, and neural correlates of ASD-like traits as well as the relationship between these dimensions in typically developing children. Parents and children completed several quantitative measures examining several areas of social-cognitive functioning, including theory of mind and social functioning, restricted/repetitive behaviors and interests, and adaptive/maladaptive functioning. Children were also asked to undergo an EEG and both parents and children contributed a saliva sample that was used to sequence four single nucleotide polymorphisms (SNPs) of the OXTR gene, rs1042778, rs53576, rs2254298, and rs237897. We successfully demonstrated a significant relationship between behavioral measures of social-cognition and differences in face perception via the N170. However, the directionality of these relationships varied based on the behavioral measure and particular N170 difference scores. We also found support for the associations between the G_G allelic combination of rs1042778 and the A_A and A_G allelic combinations of rs2254298 and increased ASD-like behavior with decreased social-cognitive functioning. In contrast, our results contradict previous findings with rs237897 and imply that individuals with the A_A and A_G genotypes are less similar to those with ASD and have higher social cognitive functioning than those with the G_G genotype. In conclusion, we have demonstrated the existence of ASD-like traits in typically developing children and have shown a link between behavioral, genetic, and neural correlates of social-cognition. These findings demonstrate the importance of considering autism as a spectrum disorder and provide support for the move to a more continuous approach to neurodevelopmental disorders.
Resumo:
Studies about transmission rates of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae in hospitals and households are scarce.
Resumo:
Pontocerebellar hypoplasia with spinal muscular atrophy, also known as PCH1, is a group of autosomal recessive disorders characterized by generalized muscle weakness and global developmental delay commonly resulting in early death. Gene defects had been discovered only in single patients until the recent identification of EXOSC3 mutations in several families with relatively mild course of PCH1. We aim to genetically stratify subjects in a large and well-defined cohort to define the clinical spectrum and genotype-phenotype correlation.