Psychiatric neuroimaging research in Brazil: historical overview, current challenges, and future opportunities

The last four decades have witnessed tremendous growth in research studies applying neuroimaging methods to evaluate pathophysiological and treatment aspects of psychiatric disorders around the world. This article provides a brief history of psychiatric neuroimaging research in Brazil, including quantitative information about the growth of this field in the country over the past 20 years. Also described are the various methodologies used, the wealth of scientific questions investigated, and the strength of international collaborations established. Finally, examples of the many methodological advances that have emerged in the field of in vivo neuroimaging are provided, with discussion of the challenges faced by psychiatric research groups in Brazil, a country of limited resources, to continue incorporating such innovations to generate novel scientific data of local and global relevance.

Progress on the application of positron emission tomography imaging of cannabinoid type 1 receptor in neuropsychiatric diseases / 浙江大学学报·医学版

Cannabinoid type 1 receptor (CB1R), as the major member of the endocannabinoid system, is among the most abundant receptors expressed in the central nervous system. CB1R is mainly located on the axon terminals of presynaptic neurons and participate in the modulation of neuronal excitability and synaptic plasticity, playing an important role in the pathogenesis of various neuropsychiatric diseases. In recent years, the consistent development of CB1R radioligands and the maturity of molecular imaging techniques, particularly positron emission tomography (PET) may help to visualize the expression and distribution of CB1R in central nervous system . At present, CB1R PET imaging can effectively evaluate the changes of CB1R levels in neuropsychiatric diseases such as Huntington's disease and schizophrenia, and its correlation with the disease severity, therefore providing new insights for the diagnosis and treatment of neuropsychiatric diseases. This article reviews the application of CB1R PET imaging in Alzheimer's disease, Parkinson's disease, Huntington's disease, schizophrenia, post-traumatic stress disorder, cannabis use disorder and depression.

Early psychiatric morbidity in a Brazilian sample of acute ischemic stroke patients

OBJECTIVE: Stroke is a major public health problem worldwide, and its neuropsychiatric sequelae are frequent and disabling. Furthermore, there is evidence that these sequelae impair recovery. Brazil has the highest stroke rates in Latin America, but data on the frequency of neuropsychiatric disorders in these patients are scarce. This study aimed to identify mental disorders among in-hospital patients with acute ischemic stroke. METHODS: The Mini International Neuropsychiatric Interview-Plus (MINI-Plus) was applied to 60 patients during the first week of hospitalization. RESULTS: Psychiatric disorders were diagnosed in 55% of the patients. A wide range of neuropsychiatric disorders have been identified, mainly mood and anxiety disorders. Specifically, we identified major depression (26.7%), alcohol abuse or dependence (11.7%), specific phobia (8.3%), generalized anxiety disorder (6.7%), psychosis (5.0%), social phobia (3.3%), adjustment disorder (3.3%) and panic disorder (1.7%). CONCLUSION: Psychiatric comorbidity should be evaluated as part of the rehabilitation of stroke patients and should be carefully examined by physicians.

Evaluation of EEG in Child Guidance Clinic.

Background: Electroencephalographic (EEG) abnormalities occur in patients with various idiopathic psychiatric disorders. Among the psychiatric patients, children have shown more EEG abnormalities as compared to the adult cases. The present study therefore examined the pattern of EEG abnormalities in children’s attending child guidance clinic of psychiatry department. Method: Electrodes were positioned according to the 10 – 20 system, using a common reference electrode. EEG recordings from 138 hospitalized psychiatric patients were graded blind to diagnosis and treatment for type of EEG abnormalities. Types of clinical diagnosis were evaluated for association with pattern EEG abnormalities. Results: EEG abnormalities occurred in 53.62% (N = 74) subjects, whereas 46.38% (N = 64) showed no abnormality in EEG record. Generalized abnormalities was observed in 37.84% (N = 28) subjects. EEG abnormality in clinically diagnosed epilepsy were commonest 64.62% (N = 42), followed by dissociative (conversion) vs. epilepsy 62.5% (N = 5), pervasive developmental disorder (PDD) 56.67% (N = 17), and mental retardation with epilepsy 28.57% (N = 10). Conclusions: EEG abnormality risk varied widely among children’s with different diagnoses referred/attending Child Guidance Clinic of psychiatry department. Risk was particularly high in clinically diagnosed epilepsy.