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Investigação sobre o mecanismo da ação antifúngica de uma osmotina de Calotropis procera contra cepas de Candida

Thu, 01 Jan 2026 00:00:00 GMT

Título: Investigação sobre o mecanismo da ação antifúngica de uma osmotina de Calotropis procera contra cepas de Candida Autor(es): Farias, Ádria Helen Pessoa Abstract: Osmotins are defense proteins (PR-5) that exhibit antifungal activity. An osmotin isolated from Calotropis procera (CpOsm) has shown activity against phytopathogenic fungi; however, its effects against Candida, a medically important yeast genus, remain poorly explored. To address this gap, this study aimed to investigate the antifungal activity and mechanism of action of CpOsm against strains of three Candida species (C. albicans, C. tropicalis, and C. auris). For this purpose, the protein was produced in Escherichia coli BL21(DE3) and purified by affinity chromatography. The recombinant osmotin (rCpOsm) exhibited antifungal activity against all strains tested, including fluconazole-resistant isolates. Minimum inhibitory concentration (MIC) values were 1.49 nM for C. albicans, 0.373 nM for C. tropicalis, and 2.99 nM for C. auris, whereas minimum fungicidal concentration (MFC) values were 2.99 nM, 1.49 nM, and 5.97 nM, respectively. rCpOsm demonstrated significant anti-biofilm activity (p < 0.05) against fluconazole-sensible and fluconazole-resistant C. auris strains, with a dual effect: inhibition of biofilm formation and disruption of mature biofilms. At 10×MIC concentration, the protein significantly reduced biomass and metabolic activity by up to 92% and 97% (biofilms in formation) and 57.5% and 86.0% (mature biofilms), as assessed by crystal violet and MTT assays. Investigation of the mechanism of action in vitro suggested that the antifungal effect on C. aurisis mediated by an interaction of rCpOsm with ergosterol in the yeast plasma membrane, as evidenced by an increase in MIC (> 10-fold) in the presence of exogenous ergosterol. Fluorescence microscopy assays revealed that CpOsm compromised membrane integrity and increased the production of reactive oxygen species in both planktonic cells and biofilms of C. auris. These cellular alterations were accompanied by changes in the protein profile of C. auris cells treated with CpOsm. Proteomic analysis revealed significant alterations in 512 proteins of C. auris, of which 505 showed an increase in abundance [Log2(fold change) > 1.5], mainly related to lipid metabolism, oxidative stress response, cell wall remodeling, and ionic homeostasis, while structural and proliferative proteins showed reduced abundance [Log2(fold change) < 0.5] or were no longer detected. Maintenance of fungicidal activity at low concentrations indicates that adaptive mechanisms are insufficient to restore cellular viability. Collectively, these findings highlight rCpOsm as a promising molecule for the development of novel antifungal strategies against clinically relevant drug-resistant pathogens. Tipo: Dissertação

A divulgação científica e a feira das profissões: uso e aplicação dessas ferramentas pedagógicas no ensino fundamental

Thu, 01 Jan 2026 00:00:00 GMT

Título: A divulgação científica e a feira das profissões: uso e aplicação dessas ferramentas pedagógicas no ensino fundamental Autor(es): Teófilo, José Wellington Leite Abstract: Vocational education in Brazil began during the Imperial period, with initiatives aimed at training young people in situations of social vulnerability. Over time, these institutions underwent successive changes, culminating in 2008 with the implementation of upper secondary education integrated with vocational education by the Brazilian Federal Government and the Government of the State of Ceará, through the Federal Institute of Education, Science, and Technology of Ceará (IFCE) and the State Schools of Vocational Education (EEEPs). The “Careers Fair” is an event that supports vocational guidance and scientific outreach within schools, assisting upper secondary students in choosing a higher education degree, while also addressing technical programs. In light of this, the following questions arise: What is the relevance of the “Careers Fair” to vocational guidance for students in the final years of lower secondary education? And how can the production and implementation of such events be encouraged within these institutions? Accordingly, the general objective of this study is to understand how the “Careers Fair” can support and motivate students, teachers, and administrators in the Municipal Education Network of Fortaleza, with the aim of incorporating it as a vocational guidance tool in the final years of lower secondary education. This research is characterized as an exploratory case study with a qualitative approach, designed to meet the stated objectives. Participants included 35 students, three teachers, and one coordinator from a part-time municipal school located in Fortaleza, Ceará. The research techniques were based on adaptations of Célestin Freinet’s methodologies, namely the “Field Trip” and “Free Text,” tailored to lower secondary education and organized into the following stages: (i) a survey of integrated upper secondary programs offered in Fortaleza, identifying 35 course options across 24 institutions; (ii) administration of a diagnostic questionnaire to students; (iii) a “Field Trip” with participants to the Careers Fair at the Federal University of Ceará (UFC), the IFCE, and one EEEP; (iv) implementation of “Free Text” activities with students; (v) semi-structured interviews with the coordinator and teachers; (vi) data analysis; and (vii) development of an Educational Product in the form of a guide entitled Scientific Outreach and the Careers Fair: Use and Application of These Pedagogical Tools in Lower Secondary Education. The results showed that 91% of students had never visited a Careers Fair; 35% were unaware of technical education options, despite reporting concerns about the labor market; among students who were aware of technical programs, Administration, Information Technology, and Nursing were the most frequently mentioned; 22.5% of students reported not yet knowing which career they wish Tipo: Dissertação

Síntese de (-)-Juvabiona e (-)-Epi-Juvabiona

Mon, 01 Jan 1990 00:00:00 GMT

Título: Síntese de (-)-Juvabiona e (-)-Epi-Juvabiona Autor(es): Vieira, Ícaro Gusmão Pinto Abstract: Juvabione, a sesquiterpene ester isolated from Balsam "Fir" (Abies balsamea (L.) Miller) shows strong juvenile hormone activity in the Pyrrhocoris apterus. [...] Tipo: Dissertação

Lectina de Dioclea guianensis (Duke) variedade Lasiophylla

Mon, 01 Jan 1990 00:00:00 GMT

Título: Lectina de Dioclea guianensis (Duke) variedade Lasiophylla Autor(es): Vasconcelos, Ilka Maria Abstract: Seeds of Dioclea guianensis Duke, var. lasiophylla contain a mannose/glucose - binding lectin which was purified by affinity chromatography on Sephadex G-50. [...] Tipo: Dissertação