Publications by authors named "Tiago Paz"

This study investigates the influence of pregnancy on the in vivo activity of the intestinal P-glycoprotein (P-gp) and hepatic organic anion transporters polypeptide (OATP/BCRP) using, respectively, fexofenadine and rosuvastatin as probe drugs. Eleven healthy participants were investigated during the third trimester of pregnancy (Phase 1, 28 to 38 weeks of gestation) and in the postpartum period (Phase 2, 8 to 12 weeks postpartum). In both phases, after administration of a single oral dose of fexofenadine (60 mg) and rosuvastatin (5 mg), serial blood samples were collected for up to 24 h.

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This study aims to evaluate the impact of liver fibrosis stages of chronic infection with hepatitis C virus (HCV) on the in vivo activity of organic cation transporters (hepatic OCT1 and renal OCT2) using metformin (MET) as a probe drug. Participants allocated in Group 1 ( = 15, mild to moderate liver fibrosis) or 2 ( = 13, advanced liver fibrosis and cirrhosis) received a single MET 50 mg oral dose before direct-acting antiviral (DAA) drug treatment (Phase 1) and 30 days after achieving sustained virologic response (Phase 2). OCT1/2 activity (MET AUC) was found to be reduced by 25% when comparing the two groups in Phase 2 (ratio 0.

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Polyketides with the isochroman-3-one pharmacophore are rare among fungal natural products as their biosynthesis requires an unorthodox S-type aromatic ring cyclization. Genome mining uncovered a conserved gene cluster in select leotiomycetous fungi that encodes the biosynthesis of cytosporones, including isochroman-3-one congeners. Combinatorial biosynthesis in total biosynthetic and biocatalytic formats in and in vitro reconstitution of key reactions with purified enzymes revealed how cytosporone structural and bioactivity diversity is generated.

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The present work reports the effects of chemical elicitors and epigenetic modifiers on the production and diversification of secondary metabolites produced by Anthostomella brabeji - an endophytic fungus isolated from Paepalanthus planifolius (Eriocaulaceae). The fungus was cultivated under four different small-scale culture conditions in potato dextrose broth (PDB): PDB (control), PDB + Mg, PDB + Cu and PDB + 5-AZA (5-azacytidine). The incorporation of Cu into PDB medium yielded the most promising results as the most significant differences in the metabolic profile of A.

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Metabolomics analyses and improvement of growth conditions were applied toward diversification of phomactin terpenoids by the fungus sp. CBMAI 1333. Visualization of molecular networking results on Gephi assisted the observation of phomactin diversification and guided the isolation of new phomactin variants by applying a modified version of chemometrics based on a fractional factorial design.

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Bioassay-guided investigation of the EtOAc-soluble extract of a culture of the marine-derived fungus sp. M16 led to the isolation of seven new polyketide- and terpenoid-derived metabolites (, , -), along with known polyketides (, -). Structures of compounds , , and - were established by analysis of spectroscopic data.

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This work aimed to evaluate the total, unbound, renal, and hepatic clearances of raltegravir (RAL) and the formation and elimination clearances of raltegravir glucuronide (RAL GLU) in pregnant women living with HIV. The participants received RAL 400 mg twice daily during the third trimester (n = 15) of gestation, delivery (n = 15), and the postpartum period (n = 8). Pharmacokinetic parameter values were calculated on the basis of plasma and urine data using noncompartmental methods.

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As part of our continuing efforts to discover new bioactive compounds from endophytic fungal sources, we have investigated the extract of the F03 strain. The study led to the isolation of four new 3-methyl-isoquinoline alkaloids (1:  - 4: ) and four known polyketides (5:  - 8: ). The structures of compounds 1:  - 4: were elucidated by 1D and 2D NMR experiments and HRMS analysis.

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Peritassa campestris (Celastraceae) root bark accumulates potent antitumor quinonemethide triterpenes (QMTs). When grown in their natural habitat, plants of the family Celastraceae produce different QMTs such as celastrol (3) and pristimerin (4). However, when they are inserted in in vitro culture systems, they accumulate maytenin (1) as the main compound.

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Essential oil from Cochlospermum regium (Schrank) Pilg. leaves (CR-EO) has been extracted by hydrodistillation; we analysed the CR-EO by gas chromatography coupled with mass spectrometry. We also conducted histochemical analysis on cross-sections of the central vein of young and adult leaves.

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Establishment of adventitious root cultures of Peritassa campestris (Celastraceae) was achieved from seed cotyledons cultured in semisolid Woody Plant Medium (WPM) supplemented with 2% sucrose, 0.01% PVP, and 4.0 mg L⁻¹ IBA.

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