Browsing by Author "Aveiro, Fernando"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
- Impacto das novas terapêuticas oncológicas no sistema endócrino Inibidores do checkpoint imunológicoPublication . Gouveia, Pedro; André, Teresa Raposo; Abreu, Silvestre; Aveiro, Fernando
- Isolated Congenital Asplenia in an Asymptomatic Patient: A Very Rare DiagnosisPublication . Dinis-Ferreira, Sofia; Lemos, Cláudia; Caldeira, Mónica; Homem-Costa, Miguel; da Luz Brazão, Maria; Aveiro, FernandoIsolated congenital asplenia is a rare condition that mostly manifests in the early years, usually due to fatal systemic infections. In this paper, however, we present a case of a 36-year-old asymptomatic patient who was referred for suspected hyposplenism, with no history of splenectomy. There were no significant changes on physical examination. Blood analysis revealed leukocytosis and thrombocytosis as well as moderate anisopoikilocytosis and red blood cells with Howell-Jolly bodies. No spleen or other malformations were identified on imaging. Individuals with isolated congenital asplenia have an increased susceptibility to invasive infections and sepsis, with rapid clinical decline and a high mortality rate despite treatment.
- Isolated Congenital Asplenia in an Asymptomatic Patient: A Very Rare DiagnosisPublication . Dinis-Ferreira, Sofia; Lemos, Cláudia; Caldeira, Mónica; Homem-Costa, Miguel; Brazão, Maria da Luz; Aveiro, FernandoIsolated congenital asplenia is a rare condition that mostly manifests in the early years, usually due to fatal systemic infections. In this paper, however, we present a case of a 36-year-old asymptomatic patient who was referred for suspected hyposplenism, with no history of splenectomy. There were no significant changes on physical examination. Blood analysis revealed leukocytosis and thrombocytosis as well as moderate anisopoikilocytosis and red blood cells with Howell-Jolly bodies. No spleen or other malformations were identified on imaging. Individuals with isolated congenital asplenia have an increased susceptibility to invasive infections and sepsis, with rapid clinical decline and a high mortality rate despite treatment.
- A Micro-Extraction Technique Using a New Digitally Controlled Syringe Combined with UHPLC for Assessment of Urinary Biomarkers of Oxidatively Damaged DNAPublication . Mendes, Berta; Silva, Pedro; Aveiro, Fernando; Pereira, Jorge; Câmara, José S.The formation of reactive oxygen species (ROS) within cells causes damage to biomolecules, including membrane lipids, DNA, proteins and sugars. An important type of oxidative damage is DNA base hydroxylation which leads to the formation of 8-oxo-7,8-dihydro-29-deoxyguanosine (8-oxodG) and 5-hydroxymethyluracil (5-HMUra). Measurement of these bio markers in urine is challenging, due to the low levels of the analytes and the matrix complexity. In order to simultaneously quantify 8-oxodG and 5-HMUra in human urine, a new, reliable and powerful strategy was optimised and validated. It is based on a semi-automatic microextraction by packed sorbent (MEPS) technique, using a new digitally controlled syringe (eVolH ), to enhance the extraction efficiency of the target metabolites, followed by a fast and sensitive ultrahigh pressure liquid chromatography (UHPLC). The optimal methodological conditions involve loading of 250 mL urine sample (1:10 dilution) through a C8 sorbent in a MEPS syringe placed in the semi-automatic eVolH syringe followed by elution using 90 mL of 20% methanol in 0.01% formic acid solution. The obtained extract is directly analysed in the UHPLC system using a binary mobile phase composed of aqueous 0.1% formic acid and methanol in the isocratic elution mode (3.5 min total analysis time). The method was validated in terms of selectivity, linearity, limit of detection (LOD), limit of quantification (LOQ), extraction yield, accuracy, precision and matrix effect. Satisfactory results were obtained in terms of linearity (r2 . 0.991) within the established concentration range. The LOD varied from 0.00005 to 0.04 mg mL21 and the LOQ from 0.00023 to 0.13 mg mL21 . The extraction yields were between 80.1 and 82.2 %, while inter-day precision (n = 3 days) varied between 4.9 and 7.7 % and intra-day precision between 1.0 and 8.3 %. This approach presents as main advantages the ability to easily collect and store urine samples for further processing and the high sensitivity, reproducibility, and robustness of eVolH MEPS combined with UHPLC analysis, thus retrieving a fast and reliable assessment of oxidatively damaged DNA