Search Results - "Vieira, Pedro"

Publication Catalog - "Vieira, Pedro"

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  1. 1

    Renal Disease in Madera Islands: twenty years experience of native kidney biopsies

    Publication
    by Vieira, Pedro
    Other Authors: Goncalves, Miguel; Durães, José; Rosa, Nuno; Resende, Luís; Silva, Gil et al.
    Renal biopsy plays an essential role either in the diagnosis or in the prognosis of patients with renal disease. In order to assess its epidemiology and evolution in Madeira Islands, we analysed twenty-seven years of native kidney biopsies. Methods: We performed a retrospective analysis of clinical records, including histological revision from 1986 to 2012, totalling 315 native kidney biopsies. They were assessed regarding the temporal evolution both for the quality/indications for renal biopsy and for the patterns of kidney disease. Results: A total of 315 native kidney biopsies were analysed. The patients’ mean age was of 40.8 ± 18.4 years and 50.5%(n = 159) were males. The most common indications for renal biopsy were nephrotic syndrome (36.2%, n = 114) and acute kidney injury (20.0%, n = 63). Among primary glomerular diseases (41.5%, n = 115) the most common were IgA nephropathy (26.1%, n = 30) and focal-segmental glomerulosclerosis (17.4%, n = 20) and among secondary glomerular diseases (31.4%, n = 87), lupus nephritis (51.7%, n = 45) and amyloidosis (20.7%, n = 18). Statistical analysis revealed significant correlation between gender and major pathological diagnosis (Fisher’s exact test, p <.01) and between indications for renal biopsy and major pathological diagnosis (χ2, p <.01). Regarding the temporal evolution, no statistically significant differences were found in the number of renal biopsies (χ2, p =.193), number of glomeruli per sample (Fisher’s exact test, p =.669), age (Kruskal-Wallis, p =.216), indications for renal biopsy (χ2, p =.106) or major pathological diagnosis groups (χ2, =.649). However, considering the specific clinico-pathological diagnoses and their temporal variation, a statistically significant difference (Fisher’s exact test, p <.05) was found for lupus nephritis and membranous nephropathy with an increasing incidence and for amyloidosis with an opposite tendency. Discussion: The review of the native kidney biopsies from a population with particular characteristics, geographically isolated, such as those from Madeira Islands, showed parallel between epidemiological numbers referring to other
    2014 article Portugal open access
  2. 2

    Situs ambiguous and absence of the inferior vena cava: an extremely rare cause of femoral hemodialysis catheter dysfunction

    Publication
    by Vieira, Pedro
    Other Authors: Rosa, Nuno G.; Castanha, Guida; Silva, Gil
    Hemodialysis catheter dysfunction (CDys) has been defined by Kidney Disease utcomes Quality Initiative (K/DOQI) guidelines as “failure to maintain an extracorporeal blood flow sufficient to perform hemodialysis without significantly lengthening the hemodialysis treatment” [1], influencing stage 5 chronic kidney disease (CKD) patients’ morbidity and mortality [2]. Among the causes of CDys, those occurring within the first 2 weeks of placement are defined as early dysfunction commonly resulting from mechanical problems, which include inadequate positioning, kinking, or constriction, while late dysfunction usually results from thrombus formation [1]. However, this case report demonstrates that one must also consider other causes of CDys.
    2015 article Portugal open access
  3. 3

    Plano real e crescimento econômico sustentável

    Publication
    by Vieira, Pedro
    Origin: Oasisbr
    TCC (graduação) - Universidade Federal de Santa Catarina. Centro Sócio-Econômico. Economia.
    2014 bachelor thesis Brazil open access
  4. 4

    Renal Disease in Madeira Islands: twenty-seven years' experience of native kidney biopsies

    Publication
    by Vieira,Pedro
    Other Authors: Goncalves,Antonio M; Duraes,Jose M; Rosa,Nuno G; Resende,Luis; Silva,Gil et al.
    Origin: SciELO Portugal
    Introduction: Renal biopsy plays an essential role either in the diagnosis or in the prognosis of patients with renal disease. In order to assess its epidemiology and evolution in Madeira Islands, we analysed twenty-seven years of native kidney biopsies. Methods: We performed a retrospective analysis of clinical records, including histological revision from 1986 to 2012, totalling 315 native kidney biopsies. They were assessed regarding the temporal evolution both for the quality/indications for renal biopsy and for the patterns of kidney disease. Results: A total of 315 native kidney biopsies were analysed. The patients’ mean age was of 40.8 ± 18.4 years and 50.5%(n = 159) were males. The most common indications for renal biopsy were nephrotic syndrome (36.2%, n = 114) and acute kidney injury (20.0%, n = 63). Among primary glomerular diseases (41.5%, n = 115) the most common were IgA nephropathy (26.1%, n = 30) and focal-segmental glomerulosclerosis (17.4%, n = 20) and among secondary glomerular diseases (31.4%, n = 87), lupus nephritis (51.7%, n = 45) and amyloidosis (20.7%, n = 18). Statistical analysis revealed significant correlation between gender and major pathological diagnosis (Fisher’s exact test, p <.01) and between indications for renal biopsy and major pathological diagnosis (χ2, p <.01). Regarding the temporal evolution, no statistically significant differences were found in the number of renal biopsies (χ2, p =.193), number of glomeruli per sample (Fisher’s exact test, p =.669), age (Kruskal-Wallis, p =.216), indications for renal biopsy (χ2, p =.106) or major pathological diagnosis groups (χ2, p =.649). However, considering the specific clinico-pathological diagnoses and their temporal variation, a statistically significant difference (Fisher’s exact test, p <.05) was found for lupus nephritis and membranous nephropathy with an increasing incidence and for amyloidosis with an opposite tendency. Discussion: The review of the native kidney biopsies from a population with particular characteristics, geographically isolated, such as those from Madeira Islands, showed parallel between epidemiological numbers referring to other European subpopulations, allowing simultaneously a comprehensive approach to our renal biopsy policies
    2014 article Portugal open access
  5. 5

    Vascular access: where are we heading?: An answer from our neighbours: an important statement

    Publication
    by Vieira,Pedro
    Other Authors: Tey,Ramon Roca; Ibeas-Lopez,José
    Origin: SciELO Portugal
    2015 other Portugal open access
  6. 6

    Malignancy after renal transplantation: a single-centre experience

    Publication
    by Vieira,Pedro
    Other Authors: Barreto,Patrícia; Pedroso,Sofia; Almeida,Manuela; Martins,La Salete; Dias,Leonídio et al.
    Origin: SciELO Portugal
    Introduction: Malignancy management in renal transplant recipients is becoming a major factor affecting long-term patient survival. Thus, we intended to evaluate both incidence and prognosis of malignant diseases following renal transplantation at a single centre in Portugal. Methods: We studied retrospectively the 2,358 patients who underwent kidney transplantation (KT) between 1983 and 2014. Apart from descriptive analysis, both demographic and clinical characteristics of cancer and non-cancer cancer patients were compared. Results: During a median follow-up of 118 (IQR 57-179) months, 139 patients (5.8%) developed 158 de novo malignancies, with a median time from KT to diagnosis of 76..5 (IQR 21.0-132.0) months. When compared to non-cancer patients, they were older at KT date, had longer graft survival and a lower living donor recipients’ prevalence. As for post-transplant malignancies analysis, the most common were non-cutaneous non-lymphomatous cancers (49.4%, n=78), skin cancers (35.4%, n=56) and post-transplant lymphoproliferative disorders (9.5%, n=15). Considering specific diagnosis, squamous cell carcinoma and basal cell carcinoma with 17.1% and 16.5% respectively, and non-Hodgkin lymphomas with 7.6%, were the most frequent. Global mortality among cancer patients was 36.0%, with a median time of 9.7 (IQR 1.9-17.5) months from time of diagnosis to death. As for survival analysis, cancer patient survival was significantly lower while censored graft survival was significantly higher in this group. Conclusion: Incidence and characteristics of malignancy following renal transplantation in our unit are similar to those globally described, despite some traits probably a result of specific ethnic and environmental characteristics
    2016 article Portugal open access
  7. 7

    Um ranking das revistas científicas especializadas em economia regional e urbana

    Publication
    by Vieira, Pedro
    Other Authors: Sousa, Lúcia
    Tendo em mente a avaliação relativa de currículos de candidatos a uma posição competitiva na subdisciplina da economia regional e urbana, por exemplo, candidatos a uma promoção ou a um financiamento, neste artigo procuramos identificar e classificar as revistas de circulação internacional especializadas nesta sub-disciplina e que são referenciadas pela base de dados bibliográfica ISI Web of Knowledge. Sendo que a classificação baseada em dados quantitativos considerada apenas traduz situações de excelência, propomos ainda uma classificação para as revistas não cobertas nesta base de dados. Como conclusão, não se observam revistas especializadas nesta sub-disciplina de classe A sendo que, em termos comparativos, as revistas de topo são B+ e têm um impacto médio 3 vezes inferior às revistas generalistas de topo que publicam artigos nesta área, i.e. a American Economic Review, a Econometrica e o Journal of Business and Economic Statistics.
    2006 article Portugal open access
  8. 8

    Lisbon mobility simulations for performance evaluation of mobile networks

    Publication
    by Vieira, Pedro
    Other Authors: Vieira, Manuel; Queluz, Maria Paula; Rodrigues, António
    In this paper a novel realistic vehicular mobility model is introduced. It captures the moving-in-groups, conscious travelling, and introduces the concept of smart travelling while following drivers’ social behavior extracted from inquiries and experimental traffic measurements. Under the model, a routing algorithm is considered. The routing algorithm minimizes the distance to a target on a step by step form, in every street crossing. This is done under a hierarchic street level structure that optimizes travel speed and quality. The mobility model was simulated for Lisbon case study and directional statistical results were compared with experimental measurements from Lisbon Municipality control center. The output shows a good correlation between simulated and experimental values.
    2005 conference output Portugal open access
  9. 9

    Improving accuracy for OTD based 3G geolocation in real urban/suburban environments

    Publication
    by Vieira, Pedro
    Other Authors: Silva, Nuno Oliveira e; Fernandes, Nuno; Rodrigues, António; Varela, Luís
    This paper presents the recent research results about the development of a Observed Time Difference (OTD) based geolocation algorithm based on network trace data, for a real Universal Mobile Telecommunication System (UMTS) Network. The initial results have been published in [1], the current paper focus on increasing the sample convergence rate, and introducing a new filtering approach based on a moving average spatial filter, to increase accuracy. Field tests have been carried out for two radio environments (urban and suburban) in the Lisbon area, Portugal. The new enhancements produced a geopositioning success rate of 47% and 31%, and a median accuracy of 151 m and 337 m, for the urban and suburban environments, respectively. The implemented filter produced a 16% and 20% increase on accuracy, when compared with the geopositioned raw data. The obtained results are rather promising in accuracy and geolocation success rate. OTD positioning smoothed by moving average spatial filtering reveals a strong approach for positioning trace extracted events, vital for boosting Self-Organizing Networks (SON) over a 3G network.
    2014 conference output Portugal restricted access
  10. 10

    Relatório de Projeto Curricular - Impactes Ambientais da Agricultura: Agricultura Convencional vs Agricultura Biológica

    Publication
    by Vieira, Pedro
    Other Authors: Almeida, José
    A agricultura é, desde os tempos remotos, uma das atividades basilares da Humanidade. As práticas agrícolas foram evoluindo, sendo tão diversificadas como as comunidades que as aplicam. Desde as sementes utilizadas ao modo de trabalhar a terra as modificações foram constantes, sempre no sentido de melhorar a quantidade e a qualidade dos alimentos. No entanto, devido ao aumento da população e à vontade de maximizar os lucros houve necessidade de aumentar a produção. Este aumento entrou numa espiral de crescimento tal que originou a degradação do meio ambiente, pois a utilização de agroquímicos e outras práticas de exploração intensiva do solo foram amplamente disseminadas, pondo em evidência a fragilidade do equilíbrio ambiental. Os principais impactes ambientais negativos, que são explanados neste trabalho, revelam a necessidade de alteração do modelo agroalimentar, sob pena de colocar em causa o abastecimento alimentar das futuras gerações e a preservação de muitas espécies da fauna e da flora. Embora existam alternativas ao modelo convencional, como a agricultura biológica, a resistência à mudança por parte dos agentes, como a classe política e dos agricultores, poderá colocar em perigo as condições propícias ao desenvolvimento da sociedade e à sobrevivência de várias espécies, cujos habitats são, diariamente, destruídos ou contaminados.
    2013 bachelor thesis Portugal open access