Browsing by Author "Coelho, A."
Now showing 1 - 7 of 7
Results Per Page
Sort Options
- Acute kidney injury with active urinary sediment analysis, a positive ANCA test and hypocomplememtemia: A tough situationPublication . Campos, A.; Vizcaíno, J.; Coelho, A.; Freitas, C.; Rocha, G.
- Angiogenesis in NSCLC: is vessel co-option the trunk that sustains the branches?Publication . Coelho, A.; Gomes, M.; Catarino, R.; Rolfo, C.; Lopes, A.; Medeiros, R.; Araújo, A.The critical role of angiogenesis in tumor development makes its inhibition a valuable new approach in therapy, rapidly making anti-angiogenesis a major focus in research. While the VEGF/VEGFR pathway is the main target of the approved anti-angiogenic molecules in NSCLC treatment, the results obtained are still modest, especially due to resistance mechanisms. Accumulating scientific data show that vessel co-option is an alternative mechanism to angiogenesis during tumor development in well-vascularized organs such as the lungs, where tumor cells highjack the existing vasculature to obtain its blood supply in a non-angiogenic fashion. This can explain the low/lack of response to current anti-angiogenic strategies. The same principle applies to lung metastases of other primary tumors. The exact mechanisms of vessel co-option need to be further elucidated, but it is known that the co-opted vessels regress by the action of Angiopoietin-2 (Ang-2), a vessel destabilizing cytokine expressed by the endothelial cells of the pre-existing mature vessels. In the absence of VEGF, vessel regression leads to tumor cell loss and hypoxia, with a subsequent switch to a neoangiogenic phenotype by the remaining tumor cells. Unravelling the vessel co-option mechanisms and involved players may be fruitful for numerous reasons, and the particularities of this form of vascularization should be carefully considered when planning anti-angiogenic interventions or designing clinical trials for this purpose. In view of the current knowledge, rationale for therapeutic approaches of dual inhibition of Ang-2 and VEGF are swiftly gaining strength and may serve as a launchpad to more successful NSCLC anti-vascular treatments.
- Genetic polymorphisms in key hypoxia-regulated downstream molecules and phenotypic correlation in prostate cancerPublication . Fraga, A.; Ribeiro, R.; Coelho, A.; Vizcaíno, J.; Coutinho, H.; Lopes, J.; Príncipe, P.; Lobato, C.; Lopes, C.; Medeiros, R.Background In this study we sought if, in their quest to handle hypoxia, prostate tumors express target hypoxia-associated molecules and their correlation with putative functional genetic polymorphisms. Methods Representative areas of prostate carcinoma (n = 51) and of nodular prostate hyperplasia (n = 20) were analysed for hypoxia-inducible factor 1 alpha (HIF-1α), carbonic anhydrase IX (CAIX), lysyl oxidase (LOX) and vascular endothelial growth factor (VEGFR2) immunohistochemistry expression using a tissue microarray. DNA was isolated from peripheral blood and used to genotype functional polymorphisms at the corresponding genes (HIF1A +1772 C > T, rs11549465; CA9 + 201 A > G; rs2071676; LOX +473 G > A, rs1800449; KDR – 604 T > C, rs2071559). Results Immunohistochemistry analyses disclosed predominance of positive CAIX and VEGFR2 expression in epithelial cells of prostate carcinomas compared to nodular prostate hyperplasia (P = 0.043 and P = 0.035, respectively). In addition, the VEGFR2 expression score in prostate epithelial cells was higher in organ-confined and extra prostatic carcinoma compared to nodular prostate hyperplasia (P = 0.031 and P = 0.004, respectively). Notably, for LOX protein the immunoreactivity score was significantly higher in organ-confined carcinomas compared to nodular prostate hyperplasia (P = 0.015). The genotype-phenotype analyses showed higher LOX staining intensity for carriers of the homozygous LOX +473 G-allele (P = 0.011). Still, carriers of the KDR−604 T-allele were more prone to have higher VEGFR2 expression in prostate epithelial cells (P < 0.006). Conclusions Protein expression of hypoxia markers (VEGFR2, CAIX and LOX) on prostate epithelial cells was different between malignant and benign prostate disease. Two genetic polymorphisms (LOX +473 G > A and KDR−604 T > C) were correlated with protein level, accounting for a potential gene-environment effect in the activation of hypoxia-driven pathways in prostate carcinoma. Further research in larger series is warranted to validate present findings.
- Hydatid Cyst Diagnosed by Endoscopic UltrasoundPublication . Castro-Poças, F.; Araújo, T.; Coelho, A.; Silva, D.; Pedroto, I.A 69-year-old female with unremarkable past history underwent endoscopy for dyspepsia. She denied weight loss or anorexia. Upper endoscopy revealed a bulge in the lesser curvature and posterior wall of the stomach with 4-5 cm. Endoscopic ultrasound was performed which showed a heterogeneous lesion, anechogenic in the major part, with a floating membrane inside, the greatest diameter of 90.8 × 17.2 mm, originated in the left liver lobe. Surgical resection was performed. Pathologic examination revealed a cystic lesion with an acellular thick fibrous wall, surrounded by a conspicuous inflammatory reaction. The cyst wall revealed a characteristic lamellar pattern of the fibers. In the internal surface of the lesion, there were remains of membranous structures, amidst which a vestigial Protoscolex was noted. In the presented case, a floating membrane was observed, which is a pathognomonic feature, establishing the diagnosis of hydatid cyst type 3. Fine needle aspiration guided by ultrasound was not performed due to the certainty in the diagnosis. To the authors' knowledge, these are the first images by endoscopic ultrasound of hydatid cyst of liver presented as a bulge in the stomach with pathognomonic features, which allowed the definitive diagnosis with no need for further diagnostic tests.
- MEMBRO FANTASMA EM AMPUTADOS DE GUERRAPublication . Cação, G.; Coelho, A.; Coimbra, D.; Massa, E.; Pacheco, L.; Pimenta, J.; Ressurreição, M.; Teixeira, J.; Romão, J.O membro fantasma é a experiência de possuir um membro ausente que se comporta similarmente ao membro real, englobando a sensação e dor. Os objectivos deste trabalho foi avaliar a prevalência da dor pós-amputação em amputados de guerra, em Portugal, e a sua caracterização. A prevalência da sensação fantasma e dor no coto e as suas implicações na dor fantasma constituem objectivos secundários, assim como o impacto da dor no quotidiano destes doentes e seu bem-estar físico e social.
- Plasmablastic lymphoma: an atypical cutaneous presentation of a rare entityPublication . Mota, F.; Mesquita, B.; Carvalho, S.; Coelho, A.; Velho, G.; Lima, M.; Selores, M.Plasmablastic lymphoma is a very rare B-cell lymphoma typically associated with immunosuppression: It occurs primarily in the oral cavity, although some cases were reported in other organs and tissues.To date, only 10 cases of primary cutaneous plasmablastic lymphoma have been described. Clinically, primary cutaneous plasmablastic lymphoma presents as non-specific cutaneous lesions (purple nodules, erythematous infiltrated plaques). In previously described cases, as in this case, histology and immunohistochemistry are required to make the diagnosis. Owing to the rarity of this entity, there is no established therapy, which makes its management an individualized, patient-based decision.
- A rare case of colonic pseudolipomatosisPublication . João-Magalhães, M.; Coelho, A.; Salgado, M.; Pedroto, I.