Percorrer por autor "Henrique, Rui"
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- Biological activities of Portuguese propolis: protection against free radical-induced erythrocyte damage and inhibition of human renal cancer cell growth in vitroPublication . Valente, Maria João; Baltazar, Ana F.; Henrique, Rui; Estevinho, Leticia M.; Carvalho, MárciaThis study reports for the first time the biological properties of Portuguese propolis. The antioxidant potential of propolis samples from Bornes (Northeast) and Fundão (Centre) regions of Portugal was evaluated by their ability to inhibit the 2,20-azobis(2-amidinopropane) dihydrochloride (AAPH)-induced oxidative hemolysis and lipid peroxidation in human erythrocytes. Bornes and Fundão propolis strongly protected the erythrocyte membrane from hemolysis (IC50 of 6.3 ± 0.7 and 10.4 ± 2.7 lg/ml, respectively), in a time- and concentration-dependent manner. This effect was found to be significantly higher than that presented by ascorbic acid (IC50 of 31.0 ± 5.6 lg/ml). In addition, human erythrocytes treated with propolis extracts showed concentration-dependent decrease in levels of malondialdehyde, a breakdown product of lipid peroxidation. Propolis extracts were also assayed for their anticancer properties on human renal cell carcinoma (RCC). Primary cultures of normal and cancerous renal cells derived from RCC patients, in addition to A-498 cell line, were treated with propolis extracts (0–100 lg/ml). Cytotoxic and antiproliferative effects were determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Propolis extracts exhibited selective toxicity against malignant cells compared to normal cells. In vitro RCC growth was strongly inhibited by Bornes and Fundão propolis in a concentration- dependent manner. Our results indicate that Portuguese propolis constitutes an excellent source of effective natural antioxidant and chemopreventive agents.
- Further insights into chemical characterization through GC–MS and evaluation for anticancer potential of Dracaena draco leaf and fruit extractsPublication . Valente, Maria João; Pinho, P. Guedes de; Henrique, Rui; Pereira, J.A.; Carvalho, MárciaThe present study reports for the first time the amino acid and fatty acid compositions and the antitumoral activity of aqueous extracts obtained from Dracaena draco L. leaf and fruit. Metabolite profiles were determined by gas chromatography-ion trap-mass spectrometry (GC-IT-MS), with several amino acids, palmitic, linolenic and stearic acid being identified in the leaf extract, and only proline, oleic and stearic acid in the fruit extract. The in vitro antiproliferative activities of the extracts were tested against human colon (Caco-2), kidney (A-498), and liver (HepG2) cancer cell lines. In addition, primary cultures of normal and cancerous renal cells derived from kidney cancer patients were treated with D. draco extracts (0-400 μg/mL). Antiproliferative and cytotoxic effects were determined by the MTT assay. D. draco extracts inhibited proliferation of human colon and renal tumor cells in vitro, whereas no or weak effect was observed in HepG2 cells. Compared to the fruit extract, D. draco leaf extract exhibited stronger antiproliferative activity against all cancer cells. Our results indicate that D. draco, particularly the leaf, may be useful as a cancer chemopreventive and/or chemotherapeutic agent for colon and kidney cancers.
- Impact of high‐risk human papilloma virus genotyping in cervical disease in the Northern region of Portugal: real‐world data from regional cervical cancer screening programPublication . Rosário, Andreia; Sousa, Ana Saraiva; Marinho-Dias, Joana; Medeiros, Rui; Lobo, Cláudia; Leça, Luís; Coimbra, Nuno; Tavares, Fernando; Baldaque, Inês; Martins, Maria Gabriela; Monteiro, Paula; Henrique, RuiCervical cancer prevention is based on primary prevention with vaccines againstHuman Papillomavirus (HPV) and secondary prevention by screening with High‐Risk‐HPV (Hr‐HPV) detection. Since 2017, cervical cancer screening in women aged25−60 years has been performed in Portugal using Hr‐HPV detection, followed bycytology in Hr‐HPV‐positive cases. Herein we report the prevalence of Hr‐HPVgenotypes and cytological abnormalities among 462 401 women (mean age:43.73 ± 10.79; median age: 45; range: 24−66 years) that participated in the RegionalCervical Cancer Screening Program of the Northern Region of Portugal, performedbetween August 2016 and December 2021. Overall, we describe a prevalence rateof 12.50% for Hr‐HPV varying from 20.76% at age 25% to 8.32% at age 64. The fivemost common Hr‐HPV genotypes identified were HPV‐68 (16.09%), HPV‐31(15.30%), HPV‐51 (12.96%), HPV‐16 (11.06%), and HPV‐39 (11.01%). Theprevalence of Hr‐HPV included in the nonavalent vaccine (HPV‐9valent) was55.00% ranging from 47.78% to 59.18% across different age groups.