Publications by authors named "Helena Brentani"

Background: Currently, there is a need for approaches to understand and manage the multidimensional autism spectrum and quantify its heterogeneity. The diagnosis is based on behaviors observed in two key dimensions, social communication and repetitive, restricted behaviors, alongside the identification of required support levels. However, it is now recognized that additional modifiers, such as language abilities, IQ, and comorbidities, are essential for a more comprehensive assessment of the complex clinical presentations and clinical trajectories in autistic individuals.

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Autism spectrum disorder (ASD) is a complex neurodevelopmental condition that combines genetic and environmental factors. The human microbiota is colonized by permanent or transitory microorganisms, depending on the host and the external factors controlling their permanence. The composition of the gut microbiota (GM) in ASD individuals is notably different from that in controls, which may contribute to the clinical conditions observed in these individuals.

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Early identification of Autism Spectrum Disorder is very important, especially in low and middle-income countries, where access to resources is often limited. The Child Behavior Checklist 1.5-5 is a tool that has been used to help identify children with autism spectrum disorder through specific behavior patterns.

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Problem: Diagnosing Autism Spectrum Disorder (ASD) remains a significant challenge, especially in regions where access to specialists is limited. Computer-based approaches offer a promising solution to make diagnosis more accessible. Eye tracking has emerged as a valuable technique in aiding the diagnosis of ASD.

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Article Synopsis
  • The study investigates how maternal immune responses during pregnancy, particularly through immune biomarkers, affect the neurodevelopment of children in their first two years of life.
  • It examines maternal psychosocial stress and childhood trauma, measuring various inflammatory markers at two gestational stages in 160 women.
  • Results indicate that specific immune profiles in late pregnancy can predict children's neurodevelopmental progress, while no direct correlation was found between maternal stress and immune markers, suggesting a complex interaction between stress and immune response in predicting neurodevelopment.
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Polygenic risk scores (PRSs) for breast cancer have a clear clinical utility in risk prediction. PRS transferability across populations and ancestry groups is hampered by population-specific factors, ultimately leading to differences in variant effects, such as linkage disequilibrium and differences in variant frequency (allele frequency differences). Thus, locally sourced population-based phenotypic and genomic data sets are essential to assess the validity of PRSs derived from signals detected across populations.

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  • Obsessive-compulsive disorder (OCD) affects about 1% of people and has a strong genetic component, but previous studies have not fully explained its genetic causes or biological mechanisms.
  • A large genome-wide association study (GWAS) analyzed data from over 53,000 OCD cases and over 2 million control participants, identifying 30 significant genetic markers related to OCD and suggesting a 6.7% heritability from SNPs.
  • The research also found 249 candidate risk genes linked to OCD, particularly in specific brain regions, and showed genetic correlations with various psychiatric disorders, laying the groundwork for further studies and potential treatments.
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Social communication skills, especially eye contact and joint attention, are frequently impaired in autism spectrum disorder (ASD) and predict functional outcomes. Applied behavior analysis is one of the most common evidence-based treatments for ASD, but it is not accessible to most families in low- and middle-income countries (LMICs) as it is an expensive and intensive treatment and needs to be delivered by highly specialized professionals. Parental training has emerged as an effective alternative.

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  • Primary human trophoblast stem cells (TSCs) and those derived from human pluripotent stem cells (hPSCs) can be modeled in the lab, but how hPSCs differentiate into TSCs is not well understood.
  • This study shows that a specific primed pluripotent state can produce TSCs by activating certain pathways (like EGF and WNT) and inhibiting others (like TGFβ and ROCK), all without adding BMP4, referred to as the TS condition.
  • The researchers found that the TSCs generated under TS conditions can proliferate extensively and closely resemble first-trimester placental cells, suggesting that primed hPSCs can differentiate into TSCs through various
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Background: Autism Spectrum Disorder (ASD) diagnosis can be aided by approaches based on eye-tracking signals. Recently, the feasibility of building Visual Attention Models (VAMs) from features extracted from visual stimuli and their use for classifying cases and controls has been demonstrated using Neural Networks and Support Vector Machines. The present work has three aims: 1) to evaluate whether the trained classifier from the previous study was generalist enough to classify new samples with a new stimulus; 2) to replicate the previously approach to train a new classifier with a new dataset; 3) to evaluate the performance of classifiers obtained by a new classification algorithm (Random Forest) using the previous and the current datasets.

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Neurodevelopment disorders can result in facial dysmorphisms. Therefore, the analysis of facial images using image processing and machine learning techniques can help construct systems for diagnosing genetic syndromes and neurodevelopmental disorders. The systems offer faster and cost-effective alternatives for genotyping tests, particularly when dealing with large-scale applications.

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  • Bipolar disorder (BD) can worsen over time for some individuals, but there is limited understanding of the molecular changes that occur as patients age.
  • In this study, researchers analyzed gene expression in the hippocampus of 11 older BD patients compared to 11 matched controls, using advanced microarray technology to identify relevant genes.
  • They found 25 genes that were mostly downregulated in BD patients, with several having previous links to BD and other psychiatric disorders, suggesting potential targets for further research into the condition's underlying mechanisms in older adults.
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Background: Despite previous studies have recently shown Autism Spectrum Disorders (ASD) as having a strong genetics background, over a minimum environmental background, no study up to date has investigated the interplay between genetics and environment.

Methods: We have collected data regarding Family History (FH) and Environmental Factors (EF) from 2,141 individuals with ASD and their caretakers throughout Brazil, based on an online questionnaire. Most of the ASD individuals were males (81%) and the average age was 02 years minimum for males and females, and the maximum age was 41 years for males and 54 for females.

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Autism spectrum disorder (ASD) is a complex neurodevelopmental condition that is characterized by patients displaying at least two out of the classical symptoms, such as impaired social communication, impaired interactions, and restricted repetitive behavior. Early parent-mediated interventions, such as video modeling for parental training, were demonstrated to be a successful low-cost way to deliver care for children with ASD. Nuclear magnetic resonance (NMR)-based metabolomics/lipidomics has been successfully employed in several mental disorder studies.

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Background: Heterogeneous mental health outcomes during the COVID-19 pandemic are documented in the general population. Such heterogeneity has not been systematically assessed in youth with autism spectrum disorder (ASD) and related neurodevelopmental disorders (NDD). To identify distinct patterns of the pandemic impact and their predictors in ASD/NDD youth, we focused on pandemic-related changes in symptoms and access to services.

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  • Maternal prenatal psychosocial stress negatively impacts the hypothalamic-pituitary-adrenal axis function in infants, with unknown biological mechanisms possibly linked to altered DNA methylation.
  • A study was conducted with 80 pregnant adolescents, measuring maternal distress via depression and anxiety, and assessing infant DNA methylation and cortisol levels at 12 months.
  • Key findings indicated that elevated maternal anxiety and cortisol levels in late pregnancy were associated with lower DNA methylation of stress-related genes in infants, particularly the oxytocin receptor gene (OXTR), which may influence stress regulation.
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Background: There is consistent evidence of the potential benefits of lithium attenuating mechanisms of neurodegeneration, including those related to the pathophysiology of Alzheimer's disease (AD), and facilitating neurotrophic and protective responses, including maintenance of telomere length. The aim was to investigate the protective effect of the pre-treatment with lithium on amyloid-beta (Aβ)-induced toxicity and telomere length in neurons.

Methods: Cortical neurons were treated with lithium chloride at therapeutic and subtherapeutic concentrations (2 mM, 0.

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Background: Physiological maternal stress response, such as imbalance in the glucocorticoid pathway and immune system seems to be mediated by DNA methylation (DNAm) and might translate intrauterine stress exposures into phenotypic changes in a sex-specific manner. DNAm in specific sites can also predict newborn gestational age and gestational age acceleration (GAA). GAA occurs when the predicted biological age is higher than the chronological age.

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Neurodevelopmental disorders differ considerably between males and females, and fetal brain development is one of the most critical periods to determine risk for these disorders. Transcriptomic studies comparing male and female fetal brain have demonstrated that the highest difference in gene expression occurs in sex chromosomes, but several autossomal genes also demonstrate a slight difference that has not been yet explored. In order to investigate biological pathways underlying fetal brain sex differences, we applied medicine network principles using integrative methods such as co-expression networks (CEMiTool) and regulatory networks (netZoo).

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MicroRNAs (miRNAs) are non-coding RNAs containing 19-26 nucleotides, and they directly regulate the translation of mRNAs by binding to them. MiRNAs participate in various physiological processes and are associated with the development of diseases, such as cancer. Therefore, understanding miRNAs regulation on targets is crucial for understanding the mechanisms of diseases and for obtaining a more suitable treatment.

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The crosstalk between maternal stress exposure and fetal development may be mediated by epigenetic mechanisms, including DNA methylation (DNAm). To address this matter, we collect 32 cord blood samples from low-income Brazilian pregnant adolescents participants of a pilot randomized clinical intervention study (ClinicalTrials.gov, Identifier: NCT02807818).

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Bipolar disorder shares symptoms and pathological pathways with other neurodegenerative diseases, including frontotemporal dementia (FTD). Since TAR DNA-binding protein 43 (TDP-43) is a neuropathological marker of frontotemporal dementia and it is involved in synaptic transmission, we explored the role of TDP-43 as a molecular feature of bipolar disorder (BD). Homogenates were acquired from frozen hippocampus of postmortem brains of bipolar disorder subjects.

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Background: Obsessive-compulsive disorder (OCD) is characterized by intrusive thoughts and repetitive actions, that presents the involvement of the cortico-striatal areas. The contribution of environmental risk factors to OCD development suggests that epigenetic mechanisms may contribute to its pathophysiology. DNA methylation changes and gene expression were evaluated in post-mortem brain tissues of the cortical (anterior cingulate gyrus and orbitofrontal cortex) and ventral striatum (nucleus accumbens, caudate nucleus and putamen) areas from eight OCD patients and eight matched controls.

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The habenula is a small epithalamic structure with widespread connections to multiple cortical, subcortical and brainstem regions. It has been identified as the central structure modulating the reward value of social interactions, behavioral adaptation, sensory integration and circadian rhythm. Autism spectrum disorder (ASD) is characterized by social communication deficits, restricted interests, repetitive behaviors, and is frequently associated with altered sensory perception and mood and sleep disorders.

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