Browsing by Author "Lopes, J."
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- Calprotectin and the Magnitude of Antibodies to Infliximab in Clinically-stable Ulcerative Colitis Patients are More Relevant Than Infliximab Trough Levels and Pharmacokinetics for Therapeutic EscalationPublication . Magro, F.; Afonso, J.; Lopes, S.; Coelho, R.; Gonçalves, R.; Caldeira, P.; Lago, P.; Sousa, H.; Ramos, J.; Gonçalves, A.; Ministro, P.; Rosa, I.; Vieira, A.; Andrade, P.; Soares, J.; Carvalho, D.; Sousa, P.; Meira, T.; Lopes, J.; Moleiro, J.; Dias, C.; Falcão, A.; Geboes, K.; Carneiro, F.Although infliximab (IFX) is an efficient therapy for ulcerative colitis (UC) patients, a considerably high rate of therapeutic failures still occurs. This study aimed at a better understanding of IFX pharmacokinetics and pharmacodynamics among clinically-asymptomatic UC patients. This was a multicentric and prospective study involving 65 UC patients in the maintenance phase of IFX therapy. There were no significant differences between patients with positive and negative clinical, endoscopic and histological outcomes concerning their IFX trough levels (TLs), area under the IFX concentration vs. time curve (AUC), clearance and antibodies to infliximab (ATI) levels. However, the need to undergo therapeutic escalation later in disease development was significantly associated with higher ATI levels (2.62μg/mL vs. 1.15μg/mL, p=0.028). Moreover, and after adjusting for disease severity, the HR (hazard ratio) for therapeutic escalation was significantly decreased for patients with an ATI concentration below 3μg/mL (HR=0.119, p=0.010), and increased for patients with fecal calprotectin (FC) level above 250μg/g (HR=9.309, p=0.018). In clinically-stable UC patients, IFX pharmacokinetic features cannot predict therapeutic response on a short-term basis. However, high levels of ATIs or FC may be indicative of a future therapeutic escalation.
- Clinical performance of an infliximab rapid quantification assayPublication . Magro, F.; Afonso, J.; Lopes, S.; Coelho, R.; Gonçalves, R.; Caldeira, P.; Lago, P.; Sousa, H.; Ramos, J.; Gonçalves, A.; Ministro, P.; Rosa, I.; Meira, T.; Andrade, P.; Soares, J.; Carvalho, D.; Sousa, P.; Vieira, A.; Lopes, J.; Dias, C.; Geboes, K.; Carneiro, F.BACKGROUND: Therapeutic drug monitoring (TDM)-based algorithms can be used to guide infliximab (IFX) adjustments in inflammatory bowel disease (IBD) patients. This study aimed to explore a rapid IFX-quantification test from a clinical perspective. METHODS: This manuscript describes a prospective cohort study involving 110 ulcerative colitis (UC) patients on the maintenance phase of IFX. IFX trough levels were quantified using a rapid quantification assay and a commonly-used reference kit. RESULTS: Irrespective of the assay used to measure IFX, its through levels were statistically different between patients with and without endoscopic remission (Mayo endoscopic score = 0), as well as between patients stratified by their faecal calprotectin (FC) levels. Despite the fact that the two methods correlated well with each other [Spearman's rank correlation coefficient = 0.843, p < 0.001; intraclass correlation coefficients = 0.857, 95% confidence interval (CI): 0.791-0.903], there was a discernible systematic variation; values obtained with the reference kit were on average 2.62 units higher than those obtained with the rapid assay. Notwithstanding, 3 µg/ml was shown to be an acceptable cut-off to assess endoscopic status and inflammatory burden levels using both assays. The percentage of patients that had a positive outcome when the IFX concentration measured by the rapid assay ranked above 3 µg/ml was 88% both for a Mayo endoscopic score ⩽ 1 and for an FC concentration <250 µg/g. CONCLUSIONS: Based on this study, we concluded that using the rapid IFX assessment system with a 3 µg/ml threshold is a reliable alternative to the time-consuming enzyme-linked immunosorbent assays in patients on the maintenance phase of IFX.
- Gastroenteropancreatic Neuroendocrine Neoplasia Characterization in Portugal: Results from the NETs Study Group of the Portuguese Society of Endocrinology, Diabetes and MetabolismPublication . Santos, A.; Vinagre, J.; Soares, P.; Claro, I.; Sanches, A.; Gomes, L.; Fernandes, I.; Catarino, A.; Preto, J.; Pereira, B.; Marques, A.; Rodrigues, F.; Amaral, C.; Rocha, G.; Mellidez, J.; Simões, H.; Lopes, J.; Bugalho, M.Background: The incidence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) has been increasing in the last five decades, but there is no large-scale data regarding these tumours in Portugal. We conducted a cross-sectional, multicentric study in main Portuguese centers to evaluate the clinical, pathological, and therapeutic profile of GEP-NENs. Methods: From November, 2012, to July, 2014, data from 293 patients diagnosed with GEP-NENs from 15 centers in Portugal was collected and registered in an online electronic platform. Results: Median age at diagnosis was 56.5 (range: 15-87) years with a preponderance of females (54.6%). The most frequent primary sites were the pancreas (31.1%), jejunum-ileum (24.2%), stomach (13.7%), and rectum (8.5%). Data regarding hormonal status was not available in most patients (82.3%). Stratified by the tumour grade (WHO 2010 classification), we observed 64.0% of NET G1, 24.7% of NET G2, and 11.3% of NEC. Poorly differentiated tumours occurred mainly in older patients (p = 0.017), were larger (p < 0.001), and presented more vascular (p = 0.004) and lymphatic (p = 0.001) invasion. At the time of diagnosis, 44.4% of GEP-NENs presented metastatic disease. Surgery (79.6%) and somatostatin analogues (30.7%) were the most frequently used therapies of GEP-NENs with reported grading. Conclusion: In general, Portuguese patients with GEP-NENs presented similar characteristics to other populations described in the literature. This cross-sectional study represents the first step to establish a national database of GEP-NENs that may aid in understanding the clinical and epidemiological features of these tumours in Portugal. Methods: From November, 2012, to July, 2014, data from 293 patients diagnosed with GEP-NENs from 15 centers in Portugal was collected and registered in an online electronic platform. Results: Median age at diagnosis was 56.5 (range: 15-87) years with a preponderance of females (54.6%). The most frequent primary sites were the pancreas (31.1%), jejunum-ileum (24.2%), stomach (13.7%), and rectum (8.5%). Data regarding hormonal status was not available in most patients (82.3%). Stratified by the tumour grade (WHO 2010 classification), we observed 64.0% of NET G1, 24.7% of NET G2, and 11.3% of NEC. Poorly differentiated tumours occurred mainly in older patients (p = 0.017), were larger (p < 0.001), and presented more vascular (p = 0.004) and lymphatic (p = 0.001) invasion. At the time of diagnosis, 44.4% of GEP-NENs presented metastatic disease. Surgery (79.6%) and somatostatin analogues (30.7%) were the most frequently used therapies of GEP-NENs with reported grading. Conclusion: In general, Portuguese patients with GEP-NENs presented similar characteristics to other populations described in the literature. This cross-sectional study represents the first step to establish a national database of GEP-NENs that may aid in understanding the clinical and epidemiological features of these tumours in Portugal.
- Genetic disruption of NRF2 promotes the development of necroinflammation and liver fibrosis in a mouse model of HFE-hereditary hemochromatosisPublication . Duarte, T.; Caldas, C.; Santos, A.; Silva-Gomes, S.; Santos-Gonçalves, A.; Martins, M.; Porto, G.; Lopes, J.In hereditary hemochromatosis, iron deposition in the liver parenchyma may lead to fibrosis, cirrhosis and hepatocellular carcinoma. Most cases are ascribed to a common mutation in the HFE gene, but the extent of clinical expression is greatly influenced by the combined action of yet unidentified genetic and/or environmental modifying factors. In mice, transcription factor NRF2 is a critical determinant of hepatocyte viability during exposure to acute dietary iron overload. We evaluated if the genetic disruption of Nrf2 would prompt the development of liver damage in Hfe(-/-) mice (an established model of human HFE-hemochromatosis).
- 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.
- Incidence and Health Related Quality of Life of Opioid-Induced Constipation in Chronic Noncancer Pain Patients: A Prospective Multicentre Cohort StudyPublication . Veiga, D.; Mendonça, L.; Sampaio, R.; Lopes, J.; Azevedo, L.High rates of opioid use for chronic noncancer pain (CNCP) have been reported worldwide, despite its association with adverse events, inappropriate use, and limited analgesic effect. Opioid-induced constipation (OIC) is the most prevalent and disabling adverse effect associated with opioid therapy. Our aim was to assess the incidence, health related quality of life (HRQOL), and disability in OIC patients.
- Prospective community-based study of stroke in Northern Portugal: incidence and case fatality in rural and urban populationsPublication . Correia, M.; Silva, M.; Matos, I.; Magalhães, R.; Lopes, J.; Ferro, J.; Silva, M.Background and Purpose—Mortality statistics indicate that Portugal has the highest stroke mortality in Western Europe. Data on stroke incidence in Northern Portugal, the region with the highest mortality, are lacking. This study was designed to determine stroke incidence and case fatality in rural and urban populations in Northern Portugal. Methods—All suspected first-ever-in-a-lifetime strokes occurring between October 1998 and September 2000 in 37 290 residents in rural municipalities and 86 023 living in the city of Porto were entered in a population-based registry. Standard definitions and comprehensive sources of information were used for identification of patients who were followed-up at 3 and 12 months after onset of symptoms. Results—During a 24-month period, 688 patients with a first-ever stroke were registered, 226 in rural and 462 in urban areas. The crude annual incidence was 3.05 (95% CI, 2.65 to 3.44) and 2.69 per 1000 (95% CI, 2.44 to 2.93) for rural and urban populations, respectively; the corresponding rates adjusted to the European standard population were 2.02 (95% CI, 1.69 to 2.34) and 1.73 (95% CI, 1.53 to 1.92). Age-specific incidence followed different patterns in rural and urban populations, reaching major discrepancy for those 75 to 84 years old, 20.2 (95% CI, 16.1 to 25.0) and 10.9 (95% CI, 9.0 to 12.8), respectively. Case fatality at 28 days was 14.6% (95% CI, 10.2 to 19.3) in rural and 16.9% (95% CI, 13.7 to 20.6) in urban areas. Conclusions—Stroke incidence in rural and urban Northern Portugal is high compared to that reported in other Western Europe regions. The high official mortality in our country, which could be explained by a relatively high incidence, was not because of a high case fatality rate.