Lívia Maria Maciel da Fonseca

Mrs. Lívia Maria Maciel da Fonseca


Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 November 2023 in Journal of Fungi
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Journal Article
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LFLívia Maria Maciel da Fonseca
Lívia Maria Maciel da Fonseca
VBVanessa Fávaro Braga
Vanessa Fávaro Braga
LTLudmilla Tonani
Ludmilla Tonani
PBPatrícia Helena Grizante Barião
Patrícia Helena Grizante Barião
ENErika Nascimento
Erika Nascimento
MKMarcia Regina von Zeska Kress
Marcia Regina von Zeska Kress
The genus Aspergillus harbors human infection-causing pathogens and is involved in the complex one-health challenge of antifungal resistance. Here, a 6-year retrospective study was conducted with Aspergillus spp. isolated from patients with invasive, chronic, and clinically suspected aspergillosis in a tertiary teaching hospital. A total of 64 Aspergillus spp. clinical isolates were investigated regarding molecular identification, biofilm, virulence in Galleria mellonella, antifungal susceptibility, and resistance to amphotericin B and azoles. Aspergillus section Fumigati (A. fumigatus sensu stricto, 62.5%) and section Flavi (A. flavus, 20.3%; A. parasiticus, 14%; and A. tamarii, 3.1%) have been identified. Aspergillus section Flavi clinical isolates were more virulent than section Fumigati clinical isolates. Furthermore, scant evidence supports a link between biofilm formation and virulence. The susceptibility of the Aspergillus spp. clinical isolates to itraconazole, posaconazole, voriconazole, and amphotericin B was evaluated. Most Aspergillus spp. clinical isolates (67.2%) had an AMB MIC value equal to or above 2 µg/mL, warning of a higher probability of therapeutic failure in the region under study. In general, the triazoles presented MIC values above the epidemiological cutoff value. The high triazole MIC values of A. fumigatus s.s. clinical isolates were investigated by sequencing the promoter region and cyp51A locus. The Cyp51A amino acid substitutions F46Y, M172V, N248T, N248K, D255E, and E427K were globally detected in 47.5% of A. fumigatus s.s. clinical isolates, and most of them are associated with high triazole MICs. Even so, the findings support voriconazole or itraconazole as the first therapeutic choice for treating Aspergillus infections. This study emphasizes the significance of continued surveillance of Aspergillus spp. infections to help overcome the gap in knowledge of the global fungal burden of infections and antifungal resistance, supporting public health initiatives.

1 January 2023 in Genetics and Molecular Biology
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Journal Article
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LOLarissa Miyuki Okano
Larissa Miyuki Okano
LFLívia Maria Maciel da Fonseca
Lívia Maria Maciel da Fonseca
IEIsabela Dias Erthal
Isabela Dias Erthal
TMTathiane Maistro Malta
Tathiane Maistro Malta
Head and Neck Cancer (HNC) is a heterogeneous group of cancers, which includes cancers arising in the oral cavity, nasopharynx, oropharynx, hypopharynx, and larynx. Epidemiological studies have revealed that several factors such as tobacco and alcohol use, exposure to environmental pollutants, viral infection, and genetic factors are risk factors for developing HNC. The squamous cell carcinoma of oral tongue (SCCOT), which is significantly more aggressive than the other forms of oral squamous cell carcinoma, presents a propensity for rapid local invasion and spread, and a high recurrence rate. Dysregulation in the epigenetic machinery of cancer cells might help uncover the mechanisms of SCOOT tumorigenesis. Here, we used DNA methylation changes to identify cancer-specific enhancers that were enriched for specific transcription factor binding sites (TFBS), and potential master regulator transcription factors (MRTF) associated with SCCOT. We identified the activation of MRTFs associated with increased invasiveness, metastasis, epithelial-to-mesenchymal transition, poor prognosis, and stemness. On the other hand, we found the downregulation of MRTFs associated with tumor suppression. The identified MRTFs should be further investigated to clarify their role in oral cancer tumorigenesis and for their potential use as biological markers.