Cancer remains a significant global health concern, with mortality rates steadily rising and prompting an urgent search for effective treatments. This study focuses on the medicinal properties of plants from the Phyllanthus genus, specifically Phyllanthus amarus and Phyllanthus niruri, which have shown promise in traditional medicine. Through bioguided fractionation using preparative high-performance liquid chromatography (HPLC), bioactive compounds were isolated and identified using ultra-performance liquid chromatography coupled to time-of-flight mass spectrometry (UHPLC-QTOF-MS) and nuclear magnetic resonance (NMR) spectroscopy.
View Article and Find Full Text PDFUnderstanding COVID-19 exposure differences among Healthcare Workers (HCWs) across various healthcare units is crucial for their protection and effective management of future outbreaks. However, comparative data on COVID-19 among HCWs in different healthcare units are scarce in Brazil. This study evaluated the relationship between SARS-CoV-2 infection and workplaces in HCWs from three distinct healthcare settings in Brazil.
View Article and Find Full Text PDFWe investigated the impact of the fourth dose with ChAdOx1 nCoV-19 (AstraZeneca) in the humoral immune response to SARS-CoV-2 during a 9-month follow-up period in which Omicron was the predominant variant in Brazil. IgG for the SARS-CoV-2 spike protein (S) and nucleocapsid (N) proteins were analyzed in samples collected before and after the fourth dose. All participants were tested monthly for SARS-CoV-2 infection by RT-qPCR.
View Article and Find Full Text PDFThe most widely used vaccines were messenger RNA (mRNA), viral vector, and inactivated virus with two-dose schedules. In Brazil, the CoronaVac (Sinovac) was the first vaccine approved for emergency use, and the third dose was administered, preferably, with the BNT162b2 vaccine. We evaluated antibody levels after 6 months of the booster dose with BNT162B2 in previous recipients of CoronaVac and whether a subsequent severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) infection enhances the antibody response.
View Article and Find Full Text PDFJ Chromatogr B Analyt Technol Biomed Life Sci
July 2019
The classical approach to drug discovery from natural products (NP's) requires strenuous and complex purification steps for the isolation and structural elucidation. Modern strategies as dereplication aim to accelerate the identification of known compounds present in a crude or partially purified extract. In this work, we investigated the influence of the solid-phase extraction (Oasis, Plexa, and Agilent C18 cartridges with and without organic modifiers) chemical profile obtained by UPLC-QTOF-MS and NMR and cytotoxicities of aqueous extracts from Phyllanthus niruri and P.
View Article and Find Full Text PDFEvid Based Complement Alternat Med
August 2016
The chemical composition and biological activity of a sample of yellow propolis from Mato Grosso do Sul, Brazil (EEP-Y MS), were investigated for the first time and compared with green, brown, and red types of Brazilian propolis and with a sample of yellow propolis from Cuba. Overall, EEP-Y MS had different qualitative chemical profiles, as well as different cytotoxic and antimicrobial activities when compared to the other types of propolis assessed in this study and it is a different chemotype of Brazilian propolis. Absence of phenolic compounds and the presence of mixtures of aliphatic compounds in yellow propolis were determined by analysing (1)H-NMR spectra and fifteen terpenes were identified by GC-MS.
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