Atividade antimicrobiana da planta Casearia sylvestris: uma revisão de literatura

Nos últimos anos, o aumento da busca por alternativas medicinais e nutricionais no campo da saúde ocasionou a busca por plantas presentes no cotidiano da população. Consequentemente, diversas pesquisas almejam avaliar o potencial e benefícios para a saúde. Portanto, o objetivo do estudo é realizar uma revisão da literatura sobre a potencial utilização medicinal e nutricional da planta Casearia sylvestris, popularmente conhecida como erva do bugre. Foram realizadas pesquisas nas bases de dados PubMed, COCHANE Library, EMBASE, Biblioteca Virtual de Saúde (BVS), Web of Science, CINAHL, utilizando os descritores selecionados no MeSH, DeCs e Entree. As buscas foram realizadas no período de junho de 2021 por três pesquisadores independentes. O critério de inclusão utilizado englobava artigos dos últimos 20 anos excluindo revisões de literatura. Após as buscas foram selecionados 12 artigos para compor a revisão de literatura. A Casearia sylvestris mostrou capacidade de atuar frente a microrganimos. Os extratos da planta foram capazes de inibir Leishmania donovani, Tripanossoma cruzi,, Candida guilliermondii, Enterococcus faecalis, Staphylococcus aureus, Streptococcus mutans, Tannerella forsythia,, Porphyromonas gingivalis, Fusobacterium nucleatum, Actinobacillus actinomycetemcomitans, Lactobacillus casei, Candida tropicalis, Tannerella forsythia, Aggregatibacter actinomycetemcomitans, Porphyromonas gingivalis, Mycobacterium tuberculosis, Lactobacilus amazonensis , Lactobacilus  braziliensis , Lactobacilus chagasi, Lactobacilus major, Escherichia coli, Salmonella setubal, Saccharomyces cerevisiae, Cryptococcus neoformans, Candida albicans, Candida glabrata, Candida krusei, Helicobacter pylori. Streptococcus oralis e Streptococcus salivarius. Assim, a Casearia Sylvestris apresenta um potencial antimicrobiano frente a alguns microrganismos, mas ainda são necessários mais estudos para uma análise mais eficiente sobre a ação contra as bactérias e uma possível aplicação clínica

Effects of subchronic dietary exposure to the engineered nanomaterials SiO and CeO in C57BL/6J and 5xFAD Alzheimer model mice.

There is an increasing concern about the neurotoxicity of engineered nanomaterials (NMs). To investigate the effects of subchronic oral exposures to SiO2 and CeO2 NMs on Alzheimer's disease (AD)-like pathology, 5xFAD transgenic mice and their C57BL/6J littermates were fed ad libitum for 3 or 14 weeks with control food pellets, or pellets dosed with these respective NMs at 0.1% or 1% (w/w). Behaviour effects were evaluated by X-maze, string suspension, balance beam and open field tests. Brains were analysed for plaque load, beta-amyloid peptide levels, markers of oxidative stress and neuroinflammation

Distinctive Toxicity of TiO₂ Rutile/Anatase Mixed Phase Nanoparticles on Caco-2 Cells

Titanium dioxide has a long-standing use as a food additive. Micrometric powders are, e.g., applied as whiteners in confectionary or dairy products. Possible hazards of ingested nanometric TiO₂ particles for humans and the potential influence of varying specific surface area (SSA) are currently under discussion. Five TiO₂-samples were analyzed for purity, crystallinity, primary particle size, SSA, ζ potential, and aggregation/agglomeration. Their potential to induce cytotoxicity, oxidative stress, and DNA damage was evaluated in human intestinal Caco-2 cells. Only anatase-rutile containing samples, in contrast to the pure anatase samples, induced significant LDH leakage or mild DNA damage (Fpg-comet assay). Evaluation of the metabolic competence of the cells (WST-1 assay) revealed a highly significant correlation between the SSA of the anatase samples and cytotoxicity. The anatase/rutile samples showed higher toxicity per unit surface area than the pure anatase powders. However, none of the samples affected cellular markers of oxidative stress. Our findings suggest that both SSA and crystallinity are critical determinants of TiO₂-toxicity toward intestinal cells

Distinctive toxicity of TiO2 rutile/anatase mixed phase nanoparticles on Caco-2 cells

Titanium dioxide has a long-standing use as a food additive. Micrometric powders are, e.g., applied as whiteners in confectionary or dairy products. Possible hazards of ingested nanometric TiO particles for humans and the potential influence of varying specific surface area (SSA) are currently under discussion. Five TiO -samples were analyzed for purity, crystallinity, primary particle size, SSA, ζ potential, and aggregation/agglomeration. Their potential to induce cytotoxicity, oxidative stress, and DNA damage was evaluated in human intestinal Caco-2 cells. Only anatase-rutile containing samples, in contrast to the pure anatase samples, induced significant LDH leakage or mild DNA damage (Fpg-comet assay). Evaluation of the metabolic competence of the cells (WST-1 assay) revealed a highly significant correlation between the SSA of the anatase samples and cytotoxicity. The anatase/rutile samples showed higher toxicity per unit surface area than the pure anatase powders. However, none of the samples affected cellular markers of oxidative stress. Our findings suggest that both SSA and crystallinity are critical determinants of TiO -toxicity toward intestinal cells

Machine learning analysis of humoral and cellular responses to SARS-CoV-2 infection in young adults

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces B and T cell responses, contributing to virus neutralization. In a cohort of 2,911 young adults, we identified 65 individuals who had an asymptomatic or mildly symptomatic SARS-CoV-2 infection and characterized their humoral and T cell responses to the Spike (S), Nucleocapsid (N) and Membrane (M) proteins. We found that previous infection induced CD4 T cells that vigorously responded to pools of peptides derived from the S and N proteins. By using statistical and machine learning models, we observed that the T cell response highly correlated with a compound titer of antibodies against the Receptor Binding Domain (RBD), S and N. However, while serum antibodies decayed over time, the cellular phenotype of these individuals remained stable over four months. Our computational analysis demonstrates that in young adults, asymptomatic and paucisymptomatic SARS-CoV-2 infections can induce robust and long-lasting CD4 T cell responses that exhibit slower decays than antibody titers. These observations imply that next-generation COVID-19 vaccines should be designed to induce stronger cellular responses to sustain the generation of potent neutralizing antibodies.ISSN:1664-322