Publications by authors named "Gabriela Xavier"

Extracellular vesicles (EVs) are produced, secreted, and targeted by most human cells, including cells that compose nervous system tissues. EVs carry several types of biomolecules, such as lipids, proteins and microRNA, and can function as signaling agents in physiological and pathological processes. In this chapter, we will focus on EVs and their cargo secreted by brain cells, especially neurons and glia, and how these aspects are affected in pathological conditions.

View Article and Find Full Text PDF
Article Synopsis
  • The study focused on developing and testing pregabalin gels for topical use in the oral cavity to treat pain.
  • Various concentrations of pregabalin were mixed with a gel base and tested for stability, thermal properties, and cytotoxic effects on human gum cells.
  • The results indicated that the gels were stable, non-toxic, and showed potential as a new treatment option for oral pain management.
View Article and Find Full Text PDF
Article Synopsis
  • Patient responses to antipsychotic drugs like risperidone vary due to clinical and genetic differences, and researchers studied ways to predict these responses in first-episode psychosis (FEP) patients.
  • The study involved 141 FEP patients who were evaluated before and after 10 weeks of treatment, with 51% considered responders based on their improvement on a specific scale.
  • Among the prediction models tested, hybrid models that combined clinical and genetic factors performed best, achieving a balanced accuracy of 72.9%, suggesting these models could improve treatment outcomes.
View Article and Find Full Text PDF

To assess the effect of bleaching with gel of pregabalin associated with 35% hydrogen peroxide on the mechanical and chemical properties and ultramorphology of dental enamel. Thirty-six (36) specimens of bovine dental incisors were obtained and divided into three groups (n = 12), namely: CG = bleaching with 35% hydrogen peroxide; KFG = bleaching with 5% potassium nitrate and 2% sodium fluoride gel + 35% hydrogen peroxide; and PGG = bleaching with experimental gel of pregabalin + 35% hydrogen peroxide. The specimens were assessed with respect to Knoop microhardness, surface roughness, and colour change, before and after bleaching.

View Article and Find Full Text PDF

Schizophrenia (SCZ) is a severe psychiatric disorder with unclear pathophysiology. Moreover, there is no specific biological marker to help clinicians to define a diagnosis, and medication is decided according to the psychiatrist's experience. In this scenario, microRNAs (miRNAs), which are small noncoding RNA molecules that regulate several genes, emerge as potential peripheral biomarkers to help not only the evaluation of the disease state but also the treatment response.

View Article and Find Full Text PDF

The pathophysiology of many neuropsychiatric disorders is still poorly understood. Identification of biomarkers for these diseases could benefit patients due to better classification and stratification. Exosomes excreted into the circulatory system can cross the blood-brain barrier and carry a cell type-specific set of molecules.

View Article and Find Full Text PDF

Enhanced phosphorus management, geared towards sustainability, is imperative due to its indispensability for all life forms and its close association with water bodies' eutrophication, primarily stemming from anthropogenic activities. In response to this concern, innovative technologies rooted in the circular economy are emerging, to remove and recover this vital nutrient to global food production. This research undertakes an evaluation of the dead-end filtration performance of a mixed matrix membrane composed of modified bentonite (MB) and polyvinylidene fluoride (PVDF) for efficient phosphorus removal from water media.

View Article and Find Full Text PDF
Article Synopsis
  • Extracellular vesicles (EVs) play a key role in biological processes like cell communication and contain microRNAs (miRNAs) linked to mental health disorders.* -
  • The study analyzed miRNA expression in serum EVs from 116 adolescents over two time points to compare those with Major Depressive Disorder, Anxiety disorders, and ADHD to those without psychiatric diagnoses.* -
  • While the longitudinal analysis showed no significant results, the cross-sectional findings indicated specific miRNA changes associated with ADHD, MDD, and ANX, highlighting their potential role in mental health. *
View Article and Find Full Text PDF

Telomeres are short tandem repeats of "TTAGGG" that protect the chromosome ends from deterioration or fusion of chromosomes. Their repeat length shortens with cell division acting as a biomarker of cellular aging. Traumatic stress events during adulthood or childhood have been associated with posttraumatic stress disorder (PTSD) and short leukocyte telomere length (LTL).

View Article and Find Full Text PDF

Schizophrenia is a severe and multifactorial disorder with an unknown causative pathophysiology. Abnormalities in neurodevelopmental and aging processes have been reported. Relative telomere length (RTL) and DNA methylation age (DMA), well-known biomarkers for estimating biological age, are both commonly altered in patients with schizophrenia compared to healthy controls.

View Article and Find Full Text PDF

Objectives: Telomeres are structures at the extremity of chromosomes that prevents genomic instability, and its shortening seems to be a hallmark of cellular aging. Past studies have shown contradictory results of telomere length (TL) in major depression, and are a few studies in late-life depression (LLD). This explores the association between TL as a molecular marker of aging and diagnosis of LLD, the severity of depressive symptoms, and cognitive performance in older adults.

View Article and Find Full Text PDF

Permeation assays are important for the development of topical formulations applied on buccal mucosa. Swine buccal and esophageal epithelia are usually used as barriers for these assays, while frozen epithelia have been used to optimize the experimental setup. However, there is no consensus on these methods.

View Article and Find Full Text PDF

We investigated the DNA methylation profile over LINE-1 in antipsychotic-naive, first-episode psychosis-patients (n = 69) before and after 2 months of risperidone treatment and in healthy controls (n = 62). Patients were evaluated using standardized scales and classified as responders and nonresponders. DNA from blood was bisulfite converted and LINE-1 fragments were amplified and pyrosequencing was performed.

View Article and Find Full Text PDF

We aimed to identify blood gene expression patterns associated to psychopathological trajectories retrieved from a large community, focusing on the emergence and remission of general psychiatric symptoms. Hundred and three individuals from the Brazilian High-Risk Cohort Study (BHRCS) for mental disorders were classified in four groups according to Child Behavior Checklist (CBCL) total score at the baseline (w0) and after 3 years (w1): low-high (L-H) (N = 27), high-low (H-L) (N = 12), high-high (H-H) (N = 34) and low-low (L-L) groups (N = 30). Blood gene expression profile was measured using Illumina HT-12 Beadchips, and paired analyses comparing w0 and w1 were performed for each group.

View Article and Find Full Text PDF

Transcutaneous electrical nerve stimulation (TENS) promotes antinociception by activating the descending pain modulation pathway and consequently releasing endogenous analgesic substances. In addition, recent studies have shown that the endocannabinoid system controls pain. Thus, the present study investigated the involvement of the endocannabinoid system in TENS-induced antinociception of cancer pain using a cancer pain model induced by intraplantar (i.

View Article and Find Full Text PDF

The impact of early life stress on mental health and telomere length shortening have been reported. Changes in brain default mode network (DMN) were found to be related to a myriad of psychiatric conditions in which stress may play a role. In this context, family environment and adverse childhood experiences (ACEs) are potential causes of stress.

View Article and Find Full Text PDF

Background: Psychiatric symptomatology during late childhood and early adolescence tends to persist later in life. In the present longitudinal study, we aimed to identify changes in genome-wide DNA methylation patterns that were associated with the emergence of psychopathology in youths from the Brazilian High-Risk Cohort (HRC) for psychiatric disorders. Moreover, for the differentially methylated genes, we verified whether differences in DNA methylation corresponded to differences in mRNA transcript levels by analyzing the gene expression levels in the blood and by correlating the variation of DNA methylation values with the variation of mRNA levels of the same individuals.

View Article and Find Full Text PDF

The study of patients with schizophrenia (SZ) at different clinical stages may help clarify what effects could be due to the disease itself, to the pharmacological treatment, or to the disease progression. We compared expression levels of targeted genes in blood from individuals in different stages of SZ: clinical high risk for psychosis (CHR), first episode of psychosis (FEP), and chronic SZ (CSZ). Then, we further verified whether single-nucleotide polymorphisms (SNPs) could be related to gene expression differences.

View Article and Find Full Text PDF

We evaluated the effects of the interaction between child maltreatment (CM) and single nucleotide polymorphisms (SNPs) on development of mental disorders (MD) and psychopathology. We genotyped 720 individuals from a Brazilian community school-based prospective study, focusing on SNPs in 21 genes known to be associated with mental disorders. CM was assessed via a multi-informant-measure, which was previously validated.

View Article and Find Full Text PDF

Study Objectives: We aimed to determine the association between short telomere length, sleep parameters, and sleep disorders in an adult general population sample.

Methods: As part of the EPISONO cohort (São Paulo, Brazil), 925 individuals answered questionnaires, underwent a full-night polysomnography and clinical assessment, and had peripheral blood collected for DNA extraction. Insomnia was diagnosed based on the Diagnostic and Statistical Manual of Mental Disorders, 4th edition; and obstructive sleep apnea was defined according to apnea-hypopnea index.

View Article and Find Full Text PDF

Child maltreatment (CM) is a global issue with serious lifelong consequences. In fact, maltreatment during childhood might be an important risk factor for the development of psychiatric disorders. Furthermore, previous studies showed a strong relationship between telomere length (TL) and early life stress.

View Article and Find Full Text PDF

Schizophrenia (SCZ) is a mental disorder arising from a complex interaction of genetic and environmental factors. It has been suggested that treatment-resistant schizophrenia (TRS) is a distinct, more severe, and homogenous subgroup of schizophrenia that could present specific biological markers. Our aim was to characterize expression of target genes in blood of TRS patients compared with non-TRS (NTRS) patients and healthy controls (HC).

View Article and Find Full Text PDF

Recent research has demonstrated that telomere maintenance might be a key integrating point for the cumulative effect of genetic and environmental factors in patients with first-episode psychosis (FEP) and schizophrenia (SCZ). Eighty-one participants with antipsychotic-naïve FEP, 173 with SCZ and 438 HC were enrolled in this study. Psychiatric diagnosis was assessed using the Semi-Structured Clinical Interview for DSM-IV Axis-I (SCID-I).

View Article and Find Full Text PDF
Article Synopsis
  • * 22 UHR participants and 88 healthy controls were involved, with telomere lengths measured using a multiplex qPCR assay.
  • * Results showed that UHR patients had significantly shorter telomere lengths than HC, suggesting potential early indicators of accelerated aging in those at risk for psychosis.
View Article and Find Full Text PDF