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Espectrometria de Massas e Molecular Networking como ferramentas para o estudo da diversidade química de espécies nativas de Passiflora L. (Passifloraceae).

2026-01-30T17:25:54Z

Título: Espectrometria de Massas e Molecular Networking como ferramentas para o estudo da diversidade química de espécies nativas de Passiflora L. (Passifloraceae). Autor(es): Garcia, Laryana Borges Primeiro Orientador: Amaral, Juliano Geraldo Abstract: The Passifloraceae family, with more than 630 species, is predominant in tropical and subtropical regions, with Passiflora being the most extensive and diverse genus. This study aims to deepen the knowledge about the Passifloraceae family and the metabolic profiles of Passiflora subspecies, known for their rich phytochemical composition, including glycosylated flavonoids, carotenoids, cyanogenic glycosides, alkaloids, steroids, lignans, fatty acids, amino acids, chlorogenic acid derivatives and proanthocyanidins. Initially, we performed a comprehensive review covering studies from 1983 to 2023, offering a detailed overview of the scientific discoveries on the chemical compounds present in the genus Passiflora. Then, we combined mass spectrometry and molecular networking to explore the chemical diversity of native species of the genus Passiflora from Brazil. We developed a comprehensive database using liquid chromatography coupled to mass spectrometry (HPLC-MS/MS) to analyze the metabolic profile of several subspecies. The generated data were submitted to the GNPS platform, which generated a Molecular Networking, in which the same substances were grouped in a single node and the similar ones in clusters. The data generated by the network were dereplicated and also analyzed by multivariate statistical methods, and thus this work revealed metabolic similarities between species, such as P. incarnata, suggesting shared pharmacological potential. We documented 25 species not previously studied, expanding the knowledge about their medicinal properties and opening paths for the development of new products. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Dissertação

Análise in silico de fatores de virulência de Chlamydia psittaci com potencial aplicação no desenvolvimento de vacinas e estudo do MHC de psitacídeos endêmicos do Brasil

2026-01-28T14:45:53Z

Título: Análise in silico de fatores de virulência de Chlamydia psittaci com potencial aplicação no desenvolvimento de vacinas e estudo do MHC de psitacídeos endêmicos do Brasil Autor(es): Teixeira, Sabrina Barbosa Primeiro Orientador: Bastos, Bruno Lopes Abstract: Chlamydia psittaci is an obligate intracellular pathogen of major zoonotic importance, widely associated with avians of the group Psittaciformes, with the potential to cause avian chlamydiosis and psittacosis in humans. The close relationship between these hosts and the infectious agent represents both a sanitary and conservation concern. The study of the Major Histocompatibility Complex (MHC) in psittacine species can serve as an important model for investigating host-pathogen interactions and the adaptive immune response of these avians, contributing to the development of strategies for the conservation of the group. This study aimed to investigate in silico the MHC of psittacine species endemic to Brazil and to perform the prediction of virulence factors and potential vaccine targets against C. psittaci. In the first chapter, 39 MHC class II sequences from Forpus passerinus and Amazona aestiva were identified and analyzed, with phylogenetic analyses indicating functional relationships with mammalian DRB and avian BL loci. Epitope prediction of the MOMP protein revealed regions with high binding affinity to MHC II molecules, including one shared between avians and mammals, suggesting potential for the development of broad-spectrum immunogens. In the second chapter, the complete proteome of a C. psittaci strain was analyzed for the identification of proteins associated with virulence, subcellular localization, and protein-protein interactions (PPI), highlighting molecular targets relevant to understanding pathogenesis and vaccine design. The results reinforce the applicability of in silico approaches in the immunogenetics of non-model species and in the search for new strategies for the prevention and control of avian chlamydiosis. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Dissertação

Análise da metilação do DNA em amostras gástricas e associação com infecção por Helicobacter pylori

2025-10-14T17:55:18Z

Título: Análise da metilação do DNA em amostras gástricas e associação com infecção por Helicobacter pylori Autor(es): Sandes, Lidiane Ferraz Primeiro Orientador: Marques, Cintia Rodrigues Abstract: Helicobacter pylori infection is a significant risk factor for the development of inflammatory and neoplasic changes in the stomach, contributing to the pathogenesis of gastric diseases, particularly through epigenetic mechanisms. This experimental study aimed to examine the DNA methylation profile of the IL6, SOCS1, MGMT, and MLH1 genes in gastric mucosal samples, considering the presence of H. pylori infection and the detection of the virulence gene cagA. Samples underwent DNA extraction, followed by sodium bisulfite conversion and analysis using the MS-HRM technique. IL6 methylation was categorized into 0-25% and 25-50%, with stratification by sex, age, and bacterial strain status. Statistical analyses included the Student’s t-test to compare mean methylation levels between H. pylori-positive and -negative groups, and chi-square or Fisher’s exact test, as appropriate, considering p < 0,05 as the significance threshold for associations between categorical variables. The results indicated that infected individual were twice as likely to exhibit moderate methylation of the IL6 gene compared to non-infected individuals (OR = 2.00; 95% CI: 0.56–7.62; p = 0.284), and those infected with cagA-positive strains had a higher risk compared to those with cagA- negative strains (OR = 1.56; 95% CI: 0.41–5.85; p = 0.508), although these differences were not statistically significant. Among men, a significant association was observed (p = 0.035), with 100% of infected individuals showing moderate methylation versus 40% in the non- infected group; no significant difference was found among women (p = 0.765). Methylation of the SOCS1 and MLH1 genes was not detected in any of the samples, regardless of infection status, while MGMT methylation was observed in only three individuals (6.82%), all at low levels, preventing statistical analysis. Although no statistically significant association was observed with cagA status, all men infected with cagA-positive strains exhibited moderate methylation. These findings suggest that H. pylori infection may modulate IL6 gene methylation, particularly in males, and underscore the role of epigenetic mechanisms in the molecular pathways underlying gastric inflammation and disease progression, especially in high- prevalence populations. Editora / Evento / Instituição: Universidade Federal da Bahia Tipo: Dissertação

Avaliação das citocinas IL-2, IL-12, IFN-y e TNF-a como preditores de mortalidade em pacientes com COVID-19 en estadi grave admitidos à unidade de terapia intensiva

2025-07-04T17:17:38Z

Título: Avaliação das citocinas IL-2, IL-12, IFN-y e TNF-a como preditores de mortalidade em pacientes com COVID-19 en estadi grave admitidos à unidade de terapia intensiva Autor(es): Brito, Gabriel Carvalho Primeiro Orientador: Melo, Fabrício Freira de Abstract: COVID-19, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS CoV-2), has caused numerous clinical manifestations that can lead to death. In a short period of time, the disease spread globally, mainly affecting individuals with comorbidities such as hypertension and diabetes. Studies demonstrate the participation of the individual's immune system in the patient's clinical evolution as well as its outcome and, therefore, the study addresses the role of certain cytokines in regulating the immune response and the comparison between them. This is a cross-sectional study, approved by the National Research Ethics Commission (CONEP) and aimed to evaluate the serum levels of Th1 response cytokines (IL-2, IL-12, INF-y and TNF-a) hospitalized. in serious condition in an intensive care unit at the Hospital Geral of Vitória da Conquista in state of Bahia. The study was carried out on 56 patients with an average of 64 years old, ranging between 16 and 97 years old, with the majority of patients being female (58.3) and, as a result, it was applied that plasma concentrations of IL-2 and INF -y are present in patients affected by COVID-19 in serious condition. Editora / Evento / Instituição: Universidade Federal da Bahia, Instituto Multidisciplinar em Saúde Tipo: Dissertação