Structural and functional brain correlates of suicidal ideation and behaviors in depression: A scoping review of MRI studies

Identifying and integrating the neural correlates of suicidal ideation and behaviors is crucial to expand the knowledge and develop targeted strategies to prevent suicide. This review aimed to describe the neural correlates of suicidal ideation, behavior and the transition between them, using different magnetic resonance imaging (MRI) modalities, providing an up-to-date overview of the literature. To be included, the observational, experimental, or quasi-experimental studies must include adult patients currently diagnosed with major depressive disorder and investigate the neural correlates of suicidal ideation, behavior and/or the transition using MRI. The searches were conducted on PubMed, ISI Web of Knowledge and Scopus. Fifty articles were included in this review: 22 on suicidal ideation, 26 on suicide behaviors and two on the transition between them. The qualitative analysis of the included studies suggested alterations in the frontal, limbic and temporal lobes in suicidal ideation associated with deficits in emotional processing and regulation, and in the frontal, limbic, parietal lobes, and basal ganglia in suicide behaviors associated with impairments in decision-making. Gaps in the literature and methodological concerns were identified and might be addressed in future studies.

The gut microbiota profile in psoriasis: a Brazilian case-control study

The pathogenesis of psoriasis, an immune-mediated chronic inflammatory skin disease, remains unclear. Studies have shown an association between psoriasis and intestinal inflammation; in this context, the influence of the gut microbiota on the immune response of psoriasis has become a focus of recent research. The present research evaluated the composition and diversity of the gut microbiota of 21 participants with psoriasis from a Brazilian referral dermatology service compared to 24 healthy controls. A stool sample was collected from each participant at the time of inclusion in the study, and the samples were analysed by sequencing the 16S rRNA gene. The recruitment of research participants involved matching between groups by sex, age, body mass index, comorbidities and smoking and the exclusion of several criteria that could potentially influence the gut microbiota and the interpretation of the data. There was an increase in the Dialister genus and Prevotella copri species in patients with psoriasis compared to the control group. A reduction in the Ruminococcus, Lachnospira and Blautia genera, as well as in the Akkermansia muciniphila species, was also verified in the psoriasis group compared to the control group. Furthermore, patients with psoriasis exhibited less gut microbiota diversity than controls.

Chemiluminescent ELISA with multi-epitope proteins to improve the diagnosis of canine visceral leishmaniasis

Diagnosing canine visceral leishmaniasis (CVL) is difficult because clinical signs of the disease are non-specific and a many infected animals in endemic areas, as in Brazil, are asymptomatic. Serological tests are the most common diagnostic methods employed, but most have limitations. For this reason, the implementation of a rapid, sensitive, and specific diagnostic test for CVL has become increasingly important. In this study, we adapted a chemiluminescent enzyme-linked immunosorbent assay (CL ELISA), using two multi-epitope recombinant proteins (PQ10 and PQ20) and a crude Leishmania antigen produced using promastigotes of L. infantum, as antigens to detect CVL infection in animals from Belo Horizonte. To investigate cross-reactions, samples from dogs with other infections (babesiosis, ehrlichiosis and Trypanosoma cruzi) were tested. Assay performance validations were conducted to analyse parameters such as variability, reproducibility, and stability. CL ELISA sensitivity/specificity with PQ10 antigen was 93.1%/80.0%; with the PQ20 protein 93.1%/96.6%; and with the crude antigen 75%/73.3%. Inter-assay variability and inter-operator coefficient of variation were <7% and <15%, with PQ10 and PQ20, respectively. The accuracy of the CL ELISA was classified as excellent for PQ10 (AUC = 0.95) and PQ20 (AUC = 0.98) and moderate for the crude antigen (AUC = 0.77). The kappa score for qualitative agreement between two plate lots was excellent for PQ10 (0.89) and good for PQ20 (0.65). PQ20 remained more stable than PQ10. The CL ELISA with recombinant proteins is a promising tool to diagnose CVL.