RESUMO
Diffusion MRI tractography (dMRI) has fundamentally transformed our ability to investigate white matter pathways in the human brain. While long-range connections have extensively been studied, superficial white matter bundles (SWMBs) have remained a relatively underexplored aspect of brain connectivity. This study undertakes a comprehensive examination of SWMB connectivity in both the human and chimpanzee brains, employing a novel combination of empirical and geometric methodologies to classify SWMB morphology in an objective manner. Leveraging two anatomical atlases, the Ginkgo Chauvel chimpanzee atlas and the Ginkgo Chauvel human atlas, comprising respectively 844 and 1375 superficial bundles, this research focuses on sparse representations of the morphology of SWMBs to explore the little-understood superficial connectivity of the chimpanzee brain and facilitate a deeper understanding of the variability in shape of these bundles. While similar, already well-known in human U-shape fibers were observed in both species, other shapes with more complex geometry such as 6 and J shapes were encountered. The localisation of the different bundle morphologies, putatively reflecting the brain gyrification process, was different between humans and chimpanzees using an isomap-based shape analysis approach. Ultimately, the analysis aims to uncover both commonalities and disparities in SWMBs between chimpanzees and humans, shedding light on the evolution and organization of these crucial neural structures.
Assuntos
Encéfalo , Pan troglodytes , Substância Branca , Pan troglodytes/anatomia & histologia , Animais , Humanos , Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Substância Branca/anatomia & histologia , Substância Branca/diagnóstico por imagem , Imagem de Tensor de Difusão , Vias Neurais/anatomia & histologia , Masculino , Especificidade da Espécie , Feminino , Processamento de Imagem Assistida por Computador , ConectomaRESUMO
The mesencephalic locomotor region (MLR) is a brain stem area whose stimulation triggers graded forward locomotion. How MLR neurons recruit downstream vsx2+ (V2a) reticulospinal neurons (RSNs) is poorly understood. Here, to overcome this challenge, we uncovered the locus of MLR in transparent larval zebrafish and show that the MLR locus is distinct from the nucleus of the medial longitudinal fasciculus. MLR stimulations reliably elicit forward locomotion of controlled duration and frequency. MLR neurons recruit V2a RSNs via projections onto somata in pontine and retropontine areas, and onto dendrites in the medulla. High-speed volumetric imaging of neuronal activity reveals that strongly MLR-coupled RSNs are active for steering or forward swimming, whereas weakly MLR-coupled medullary RSNs encode the duration and frequency of the forward component. Our study demonstrates how MLR neurons recruit specific V2a RSNs to control the kinematics of forward locomotion and suggests conservation of the motor functions of V2a RSNs across vertebrates.
Assuntos
Mesencéfalo , Peixe-Zebra , Animais , Larva , Mesencéfalo/fisiologia , Locomoção/fisiologia , Neurônios/fisiologia , Medula Espinal/fisiologia , Estimulação ElétricaRESUMO
Brain folding patterns vary within the human species, but some folding properties are common across individuals, including the Sylvian fissure's inter-hemispheric asymmetry. Contrarily to the other brain folds (sulci), the Sylvian fissure develops through the process of opercularization, with the frontal, parietal, and temporal lobes growing over the insular lobe. Its asymmetry may be related to the leftward functional lateralization for language processing, but the time course of these asymmetries' development is still poorly understood. In this study, we investigated refined shape features of the Sylvian fissure and their longitudinal development in 71 infants born extremely preterm (mean gestational age at birth: 26.5 weeks) and imaged once before and once at term-equivalent age (TEA). We additionally assessed asymmetrical sulcal patterns at TEA in the perisylvian and inferior frontal regions, neighbor to the Sylvian fissure. While reproducing renowned strong asymmetries in the Sylvian fissure, we captured an early encoding of its main asymmetrical shape features, and we observed global asymmetrical shape features representative of a more pronounced opercularization in the left hemisphere, contrasting with the previously reported right hemisphere advance in sulcation around birth. This added novel insights about the processes governing early-life brain folding mechanisms, potentially linked to the development of language-related capacities.
Assuntos
Lateralidade Funcional , Recém-Nascido Prematuro , Lactente , Humanos , Recém-Nascido , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Encéfalo/anatomia & histologiaRESUMO
Antimicrobial resistance is a major global health threat and its development is promoted by antibiotic misuse. While disk diffusion antibiotic susceptibility testing (AST, also called antibiogram) is broadly used to test for antibiotic resistance in bacterial infections, it faces strong criticism because of inter-operator variability and the complexity of interpretative reading. Automatic reading systems address these issues, but are not always adapted or available to resource-limited settings. We present an artificial intelligence (AI)-based, offline smartphone application for antibiogram analysis. The application captures images with the phone's camera, and the user is guided throughout the analysis on the same device by a user-friendly graphical interface. An embedded expert system validates the coherence of the antibiogram data and provides interpreted results. The fully automatic measurement procedure of our application's reading system achieves an overall agreement of 90% on susceptibility categorization against a hospital-standard automatic system and 98% against manual measurement (gold standard), with reduced inter-operator variability. The application's performance showed that the automatic reading of antibiotic resistance testing is entirely feasible on a smartphone. Moreover our application is suited for resource-limited settings, and therefore has the potential to significantly increase patients' access to AST worldwide.
Assuntos
Inteligência Artificial , Resistência Microbiana a Medicamentos , Testes de Sensibilidade Microbiana/métodos , Aplicativos Móveis , Smartphone , Antibacterianos/farmacologia , Infecções Bacterianas , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Humanos , Processamento de Imagem Assistida por Computador , Aprendizado de Máquina , SoftwareRESUMO
Migration is a complex phenomenon and mental illness among immigrants remains a major matter of concern in Italy and worldwide. 243 medical and pharmacy records of patients admitted to University of Foggia hospital between 2004 and 2018 were retrospectively screened and included in the study. Socio-demographic data and clinical characteristics of inpatients were compared in those with and without first-episode of mental illness (FEMI). Subjects (140 men, 103 women; aged 34.4 ± 10.2 years) represented 6.66 ± 3.73% of all hospitalizations in 15 years. Nearly half of them (48.5%) had emigrated from other European countries. 30.8% were diagnosed with a DSM-IV TR unspecified psychosis. 103 patients (42.3%) were in first-lifetime episodes of mental illness. Factors significantly associated with FEMI were: younger age, sex (men), immigrating from Africa, poor language proficiency, lower amount of prescribed psychotropics. Mental health among immigrants is of major concern in Italy. Our findings report on factors possibly associated to the onset of mental illness among immigrant psychiatric inpatients.
Assuntos
Transtornos Mentais , Transtornos Psicóticos , Migrantes , Feminino , Humanos , Itália/epidemiologia , Masculino , Transtornos Mentais/epidemiologia , Estudos RetrospectivosRESUMO
AIM: The DSM-5 has modified the diagnostic criteria for gambling disorder, compared to the fourth edition of the manual; new diagnostic instruments are therefore needed. This study evaluated the psychometric characteristics of the Gambling Disorder Screening Questionnaire (GDSQ), a self-report questionnaire based on the DSM-IV and DSM-5 criteria for Gambling Disorder, measuring its validity, internal consistency, and submitting the questionnaire to a principal components analysis. METHODS: 71 patients from a gambling disorder outpatient clinic and 70 controls were evaluated with the GDSQ, the South Oaks Gambling Screen (SOGS), and a psychiatric interview. RESULTS: The test showed a good sensibility, specificity, internal consistency, concurrent validity with the SOGS. The exclusion of the "illegal acts" item, and the lowering of the cut-off score to four positive items, as suggested by the DSM-5 criteria, improved the test sensibility and internal consistency. DISCUSSION AND CONCLUSIONS: The GDSQ can be considered a useful screening test for Gambling Disorder. Furthermore, this study confirms the improved diagnostic accuracy of the criteria listed in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, compared to the previous edition.
Assuntos
Jogo de Azar/diagnóstico , Testes Psicológicos , Inquéritos e Questionários , Adulto , Instituições de Assistência Ambulatorial , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Autorrelato , Sensibilidade e EspecificidadeRESUMO
We characterize, experimentally, the intensity minima of a polarized high numerical aperture optical speckle pattern and the topological charges of the associated optical vortices. The negative of a speckle pattern is imprinted in a uniform fluorescent sample by photobleaching. The remaining fluorescence is imaged with superresolution stimulated emission depletion microscopy, which reveals subdiffraction fluorescence confinement at the center of optical vortices. The intensity statistics of saturated negative speckle patterns are predicted and measured. The charge of optical vortices is determined by controlling the handedness of circular polarization, and the creation or annihilation of a vortex pair along propagation is shown.
RESUMO
In this paper we report a systematic XAS study of a set of samples in which Cu(II) was progressively added to complexes in which Zn(II) was bound to the tetra-octarepeat portion of the prion protein. This work extends previous EPR and XAS analysis in which, in contrast, the effect of adding Zn(II) to Cu(II)-tetra-octarepeat complexes was investigated. Detailed structural analysis of the XAS spectra taken at both the Cu and Zn K-edge when the two metals are present at different relative concentrations revealed that Zn(II) and Cu(II) ions compete for binding to the tetra-octarepeat peptide by cross-regulating their relative binding modes. We show that the specific metal-peptide coordination mode depends not only, as expected, on the relative metal concentrations, but also on whether Zn(II) or Cu(II) was first bound to the peptide. In particular, it seems that the Zn(II) binding mode in the absence of Cu(II) is able to promote the formation of small peptide clusters in which triplets of tetra-octarepeats are bridged by pairs of Zn ions. When Cu(II) is added, it starts competing with Zn(II) for binding, disrupting the existing peptide cluster arrangement, despite the fact that Cu(II) is unable to completely displace Zn(II). These results may have a bearing on our understanding of peptide-aggregation processes and, with the delicate cross-regulation balancing we have revealed, seem to suggest the existence of an interesting, finely tuned interplay among metal ions affecting protein binding, capable of providing a mechanism for regulation of metal concentration in cells.
Assuntos
Cobre/farmacologia , Príons/química , Príons/metabolismo , Zinco/metabolismo , Sequência de Aminoácidos , Relação Dose-Resposta a Droga , Dados de Sequência Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Ligação Proteica/efeitos dos fármacosRESUMO
BACKGROUND: Nowadays, adult separation anxiety disorder (ASAD) is an established diagnostic category but is little investigated in subjects with addictive behaviours. OBJECTIVE: To assess the presence of ASAD among patients with addictive disorders in comparison with anxiety patients and measure the personality correlates in all these groups. METHODS: 103 outpatients, meeting DSM-IV-TR criteria for anxiety disorders (38 patients), alcohol dependence (30 patients), or pathological gambling (35 patients), were assessed by the Structured Clinical Interview for Separation Anxiety Symptoms (SCI-SAS) and the Adult Separation Anxiety Checklist (ASA-27) for separation anxiety and by the Temperament and Character Inventory-Revised (TCI-R) for personality characteristics. RESULTS: ASAD is detected in 34.2% of anxiety patients, 13.3% of alcoholics, and 11.4% of gamblers. Separation anxiety scores correlate positively with harm avoidance and negatively with self-directedness in all groups; further correlations are seen among addictive patients only, that is, self-transcendence for gamblers and cooperativeness for both alcoholics and gamblers. CONCLUSIONS: The prevalence of ASAD is lower among addictive patients than in those with anxiety disorders; correlations are found between separation anxiety and specific TCI-R dimensions, with some matching across the three diagnostic groups.
Assuntos
Alcoolismo/diagnóstico , Ansiedade/diagnóstico , Comportamento Aditivo , Jogo de Azar/diagnóstico , Adulto , Alcoolismo/fisiopatologia , Ansiedade/fisiopatologia , Feminino , Jogo de Azar/fisiopatologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Since the mid-90s several studies have proven the existence of an Adult form of the Separation Anxiety Disorder (ASAD) not yet nosologically recognized by the international psychiatric classification systems (DSM and ICD). An increasing amount of evidence showed that the separation anxiety disorder may arise at any age, not always in continuation with the correspondent childhood disorder. So, a revision of the diagnostic criteria for this disorder is brought into question, as the onset is currently limited before 18 years of age. Different tools have been developed for the assessment of ASAD: 1) the Adult Separation Anxiety Structured Interview (ASA-SI), a semi-structured interview with items derived and adapted from the DSM-IV-TR childhood disorder; 2) the Adult Separation Anxiety-27 (ASA-27), a self-administered rating scale containing the same items of ASA-SI; 3) the Structured Clinical Interview for Separation Anxiety Symptoms (SCI-SAS), a structured interview including two specific forms for childhood and adulthood. However, according to available evidence, the separation anxiety may be a dimension with cross-nosographical presentation in nearly all the commonest mood and anxiety disorders; moreover, it is connected to greater personal dysfunction and lower responsiveness to treatment. Furthermore, a deeper comprehension of the psychobiological nature of separation anxiety should lead to newer and more effective therapeutic intervention. Literature is reviewed awaiting the publication of DSM-V.