Encontrados 25 documentos, a visualizar página 1 de 3
A first-in-class inhibitor of homologous recombination DNA repair counteracts t...
Calheiros, Juliana; Silva, Rita; Barbosa, Filipa; Morais, João; Moura, Sara Reis; Almeida, Sofia; Fiorini, Elena; Mulhovo, Silva; Aguiar, Tatiana QuintaBackground Pancreatic ductal adenocarcinoma (PDAC) is among the cancer types with poorest prognosis and survival rates primarily due to resistance to standard-of-care therapies, including gemcitabine (GEM) and olaparib. Particularly, wild-type (wt)BRCA tumours, the most prevalent in PDAC, are more resistant to DNA-targeting agents like olaparib, restraining their clinical application. Recently, we disclosed a m...
Redefining ovarian cancer treatment with a first-in-class inhibitor of homologo...
Saraiva, Lucília H.; Pardal de Matos, Ana C.; Mota, Inês; Moura, Sara; Ciucci, Alessandra; Aguiar, Tatiana Quinta; Ricardo, Sara; Almeida, Maria I.Background: High-grade serous ovarian cancer (HGSOC) is characterized by poor prognosis and low overall survival. While PARP inhibitors (PARPis) are standard maintenance therapy for BRCA-mutated HGSOC (10% of cases), acquired resis-tance develops in over 60% of patients. We identied BBIT20, a rst-in-class inhibitor of the BRCA1-BARD1 interaction that disrupts homologous recombination (HR) DNA repair. Methods: B...
Triterpenoids from Momordica balsamina: modulation of ABCB1 mediated Multidrug ...
Ramalhete, Cátia; Molnar, Joseph; Mulhovo, Silva; Ferreira, Maria JoséThe ability as P-glycoprotein (P-gp, ABCB1) modulators of thirty (1-30) triterpenoids of the cucurbitane-type was evaluated on human L5178 mouse T-lymphoma cell line transfected with the human MDR1 gene, through the rhodamine-123 exclusion assay. Compounds (1-26, and 29, 30) were previously obtained from the African medicinal plant Momordica balsamina, through both isolation (1-15) and molecular derivatization ...
Triterpenoids from Momordica balsamina with a Collateral Sensitivity Effect for...
Ramalhete, Cátia; Mulhovo, Silva; Lage, Hermanm; Ferreira, Maria JoséThe collateral sensitivity effect is among the most promising strategies for overcoming multidrug resistance in cancer. In this work, 28 cucurbitane-type triterpenoids (1: -28: ), previously isolated from the African medicinal plant Momordica balsamina and its derivatives, were evaluated for their collateral sensitivity effect on three different human cancer entities, gastric (EPG85-257), pancreatic (EPP85-181)...
Dual-stage triterpenoids from an African medicinal plant targeting the malaria ...
Ramalhete, Cátia; Pimpão da Cruz, Filipa; Mulhovo, Silva; Sousa, Inês; Fermandes, M. X.; Prudêncio, Miguel; Ferreira, Maria JoséSixteen triterpenoids (1-16), previously isolated from the aerial parts of the African medicinal plant Momordica balsamina or obtained by derivatization, were evaluated for their activity against liver stages of Plasmodium berghei, measuring the luminescence intensity in Huh-7 cells infected with a firefly luciferase-expressing P. berghei line, PbGFP-Luccon. Toxicity of compounds (1-16) was assessed on the same...
In vitro schistosomicidal activity of balsaminol F and karavilagenin C.
Ramalhete, Cátia; Magalhães, L. G.; Rodrigues, V.; Mulhovo, Silva; Da Silva Filho, A. A.; Ferreira, Maria JoséFive cucurbitane-type triterpenes (1-5), previously isolated from the African medicinal plant Momordica balsamina, along with five ester derivatives (6-10) of karavilagenin C (2), were evaluated for their potential schistosomicidal activity against Schistosoma mansoni adult worms. The natural compounds were isolated from the ethyl acetate-soluble fraction of the methanol extract of the aerial parts of M. balsam...
Antibacterial activity of some African medicinal plants used traditionally agai...
Madureira, Ana Margarida; Ramalhete, Cátia; Mulhovo, Silva; Duarte, Aida; Ferreira, Maria JoséCONTEXT: Plants are known to play a crucial role in African traditional medicine for the treatment of infection diseases. OBJECTIVES: To investigate the claimed antimicrobial properties of plants traditionally used in African countries, providing scientific validation for their use. MATERIALS AND METHODS: Eighty-three polar and non-polar extracts from 22 medicinal plants were screened for their antibacterial ac...
Triterpenoids as inhibitors of erythrocytic and liver stages of Plasmodium infe...
Ramalhete, Cátia; Pimpão da Cruz, Filipa; Lopes, Dinora; Mulhovo, Silva; Rosário, Virgilio Estólio; Prudêncio, Miguel; Ferreira, Maria JoséBioassay-guided fractionation of the methanol extract of Momordica balsamina led to the isolation of two new cucurbitane-type triterpenoids, balsaminol F (1) and balsaminoside B (2), along with the known glycosylated cucurbitacins, cucurbita-5,24-diene-3β,23(R)-diol-7-O-β-D-glucopyranoside (3) and kuguaglycoside A (4). Compound 1 was acylated yielding two new triesters, triacetylbalsaminol F (5) and tribenzoylb...
Karavilagenin C derivatives as antimalarials.
Ramalhete, Cátia; Lopes, Dinora; Molnar, Joseph; Mulhovo, Silva; Rosário, Virgilio Estólio; Ferreira, Maria JoséKaravilagenin C (1), a cucurbitane-type triterpenoid, previously isolated from the aerial parts of Momordica balsamina, was acylated with different alkanoyl, aroyl and cinnamoyl chlorides/anydrides, yielding ten new mono or diesters, karavoates F (7) and H-P (8-16). Furthermore, the new compound cucurbalsaminol C (17) was isolated from the same plant. Their structures were assigned by spectroscopic methods, inc...
Inhibition of efflux pumps in methicillin-resistant Staphylococcus aureus and E...
Ramalhete, Cátia; Spengler, Gabriela; Martins, Ana; Martins, Marta; Viveiros, Miguel; Mulhovo, Silva; Ferreira, Maria José; Amaral, LeonardSix cucurbitane-type triterpenoids (1-6) isolated from the aerial parts of Momordica balsamina were evaluated for their ability to inhibit the activity of bacterial efflux pumps of methicillin-resistant Staphylococcus aureus (MRSA) COL(OXA), Enterococcus faecalis ATCC 29212, Salmonella enterica subsp. I serovar Typhimurium 5408 and S. Typhimurium 5408CIP strains. The latter strain overproduces the AcrB transpor...