2,858 research outputs found

    Desmoid Tumours in Familial Adenomatous Polyposis: Review of 17 Patients from a Portuguese Tertiary Center

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    INTRODUCTION: Desmoid Tumours (DT) are benign tumours with an estimated incidence of 2-4 per million per year. Between 7-16% of them are associated with Familial Adenomatous Polyposis (FAP) and are mostly parietal or intra-abdominal. They are a challenge in relation to their unpredictable natural course, associated complications and difficult treatment. AIM: The aim of the present study was to review the occurrence, management and follow-up of DT on FAP patients treated consecutively at a tertiary care center. MATERIALS AND METHODS: A retrospective review of clinical data from patients treated consecutively between 1993 and 2014. Patients' data was gathered from clinical records. Data collection included the following variables: demographic data, genotype, FAP phenotype, data on FAP related surgery, DT diagnosis, location, size and number, DT treatment, patients' status and follow-up data. RESULTS: The study population consisted of 17 patients from 9 families; with a mean age of 41 years, mostly women (59%) and most with a mutation either on codon 232 or 554. Most tumours had an intra-abdominal component (59%) with a mean size of 5cm. Fifteen patients were first treated with pharmacotherapy (Non-steroidal Anti-inflammatory Drugs (NSAIDs) and Tamoxifen). Five patients (29%) underwent surgery, 4 of them for complications of intra-abdominal tumours and 1 patient for abdominal wall tumours. Two patients underwent chemotherapy in relation to aggressive intra-abdominal disease. The mean follow-up time since diagnosis of DT was 123 months. Overall, 2 patients had remission, 11 patients had regression or stabilized disease, and 2 patients had progression. One patient died due to surgical complications. CONCLUSION: Diagnosis of DT is based on clinical symptoms, without the need for screening, although imaging plays an important role once diagnosis is suspected. The treatment approach is conservative on most patients, leaving surgery for DT related complications. The follow-up of patients with DT is also based on clinical symptoms.info:eu-repo/semantics/publishedVersio

    Shelf-Ocean material exchange influencing the Atlantic chemical composition off NW Iberian margin since the last glaciation

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    Rivers are the main conduit of sediment to the shelf. The basin geology, the drainage area and the discharge rate are the major factors that determine their sediment load (Milliman and Syvistski, 1992). Besides suspended particles, dissolved components may also give some information on the eroded crust. Sr isotopes in carbonate shells of biological organisms have been used to study, in the geological record, the influence exerted by the chemical weathering of the continental crust on the seawater composition (Macdougall, 1991). In this work, Sr isotope ratios obtained in tests of foraminifera representing the last 40 ka are presented and discussed in the scope of the palaeogeographical evolution of NW Iberia. This work aims to present and discuss the results of Sr isotope analyses (performed, by TIMS, in the Isotope Geology Laboratory of the University of Aveiro) of tests of two species of foraminifera, from nine samples taken along the OMEX core KC 024-19 (181 cm; 42°08’98’’N, 10°29´96’’W, and 2765m), collected in the Galicia Bank area, off Galicia. Taking into account that Sr contained in the carbonate tests is usually considered as preserving the signature of the contemporaneous seawater, one planktonic species (Globigerina bulloides) and one benthic species (Cibicides wuellerstorfi) were selected in order to try to detect Sr isotope variations both through time and between two different levels of the water column. The core age model, which records the last 40 ka, is based on a combination of oxygen isotope stratigraphy, eight AMS 14C datings and the synchronisation of the last four Heinrich Events in the Iberian Margin sedimentary records. As a whole, the obtained 87Sr/86Sr ratios vary between 0.709209 and 0.709108, with a mean 2σ error of 0.000025. These values lie within the range of modern marine Sr isotope ratios (0.70910-0.70922), as previously defined using analyses of both seawater and marine carbonates (see compilation by Faure and Mensing, 2005). Despite their small variation, the 87Sr/86Sr ratios obtained in G. bulloides seem to indicate that Sr dissolved in seawater at the KC 024-19 core site became slightly less radiogenic after the Last Glacial Maximum (LGM). This decrease is concomitant with diminishing amounts of the detrital components in the sediments (Fig. 1). Therefore, both the composition of dissolved Sr, as revealed by results on tests of planktonic foraminifera, and the proportions of suspended terrigenous particulate material arriving at the KC 024-19 site point to a decreasing importance of the contribution of the erosion of the Iberian Variscan crust since the Last Glacial Maximum and in the Holocene. The 87Sr/86Sr ratios measured in tests of benthic foraminifera (C. wuellerstorfi) are more erratic and no correlation can be established with palaeogeographical/palaeoclimatic constraints. The difference between the behaviour of Sr compositions in G. bulloides and C. wuellerstorfi may indicate that whilst the planktonic foraminifera should reproduce very closely the seawater composition, the benthic organisms should, in addition to the major role of seawater, also be affected by some sort of interaction with the sediments. As such, planktonic foraminifera are probably more reliable indicators of seawater composition in studies involving very small periods and corresponding very slight variations of the 87Sr/86Sr ratios. Taking into account that G. bulloides is a common planktonic species (living mostly in the first 50m of the water column), whose tests seem to be in equilibrium with sea water composition, variations in its 87Sr/86Sr ratios can be related with changes in the chemical composition of the water of the Atlantic Ocean off NW Iberian Margin. The highest 87Sr/86Sr values are contemporaneous with a period of low sea level (about -140 m; Dias et al., 2000) during the LGM. According to Dias et al. (2000) at 18 ka BP the shoreline was close to the shelf break. The summital parts of the Gerês and Estrela mountains were covered by local glaciers and close to the coast freezing occurred frequently. The river catchments, which extended far to the shelf, received more rainfall due to a longer, compared to present day conditions, wet season, which promoted both physical and chemical weathering. Higher pluviosity combined with the effect of spring ice melting maintained high river discharge and consequently caused very important sediment supply to the coastal zone. The extremely narrow shelf was a very energetic environment due to sea bottom inclination and very limited long wave refraction. Therefore, at that time, a long wet season and very competent rivers should have caused important erosion of the Variscan basement in NW Iberia. Additionally, then, the shoreline was much closer to the KC 024-19 site. The combination of all these factors favoured an important deposition of terrigenous sediments and the local slight enrichment in radiogenic Sr of the seawater. With sea level rise, after the deglaciation and during the Holocene, the river estuaries became progressively far away from the shelf break. Their competence of transport also became progressively reduced and the offshore transport of detrital sediments became progressively lower. Conversely the biogenic carbonate proportion in the sediments increased, due to lower dilution by the terrigenous particles. Simultaneously, the values of 87Sr/86Sr in the seawater at the KC 024-19 site became lower, as a consequence of a complete homogenization with the ocean global composition, which was now more effective with the increasing distance towards shoreline

    Colite a CMV Mimetizando Tumor Rectal num Doente com VIH Não Diagnosticado

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    Introduction: Cytomegalovirus (CMV) is the most common opportunistic agent in HIV-infected patients. It can affect the entire gastrointestinal tract, but frequently involves the oesophagus and the colon. Case Report: We report the case of a 70-year-old female, ultimately diagnosed with HIV infection, whose inaugural clinical manifestation was CMV colitis with endoscopic findings resembling a rectal tumour in which initial histological evaluation was not able to provide a proper diagnosis. Discussion/Conclusion: Since clinical presentation is variable and histopathological yield without immunohistochemical analysis is poor, recognizing CMV infection in the absence of known risk factors may be difficult. It is crucial to consider this entity with suspicious lesions or when initial evaluation, either clinical or histopathological, is inconclusive, thus avoiding potentially debilitating and superfluous treatment or life-threatening complications.info:eu-repo/semantics/publishedVersio

    Investigating exclusive ρ0\rho^0 photoproduction within the Regge phenomenology approach

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    The elastic differential and integrated total cross section for the exclusive ρ0\rho^0 photoproduction in electron-proton (epep) collisions are evaluated taking into account nonperturbative Pomeron exchange approach. By using three different models based on Regge phenomenology the results are compared to recent measurements by H1 Collaboration in epep collisions and by the CMS collaboration from ultraperipheral proton-lead collisions. The analysis is expanded by calculating the coherent nuclear cross section, σ(γAρ0A)\sigma (\gamma A\rightarrow \rho^0 A), which is applied to ρ0\rho^0 production in ultraperipheral lead-lead and xenon-xenon collisions. The predictions are compared to the measurements performed by ALICE Collaboration. Aspects of the theoretical uncertainties and limitations of the formalism are scrutinized

    Efeitos de Caracteres Físicos e Químicos Sobre o Teor de Óleo de Frutos de Pupunha.

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    O objetivo deste estudo foi avaliar a relação entre variáveis físicas e químicas de frutos de pupunha, apontando os efeitos diretos e indiretos de variáveis explicativas sobre a variável principal, teor de óleo

    Relações Causa-Efeito entre Caracteres Físicos e Químicos sobre Teor de Fibras em Frutos de Pupunha.

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    O objetivo deste trabalho foi quantificar e caracterizar a relação entre caracteres explicativos físicos e químicos de frutos de pupunha sobre o caráter tido como principal, percentual de fibra. Desejou-se, também, compreender a inter-relação entre dois complexos de variáveis, químicas e físicas, associadas ao fruto

    Tilt Training Increases Vasoconstrictor Reserve in Patients with Neurocardiogenic Syncope

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    A síncope neurocardiogénica (SNc) é uma entidade clínica comum, resultante de uma resposta autonómica reflexa excessiva durante o stress ortostático. As diferentes opções terapêuticas são controversas e de eficácia limitada. O treino de ortostatismo (TTr) tem-se mostrado uma alternativa prometedora no tratamento destes doentes (D). No entanto, permanece por esclarecer o seu mecanismo de acção e o impacto clínico numa população com SNc recorrente. Objectivo: Caracterizar a resposta hemodinâmica e autonómica durante um programa de TTr em doentes com SNc refratária às medidas convencionais. População e métodos: Foram estudados 28D (50% do sexo masculino, 41±14 anos), sem evidência de cardiopatia, com SNc documentada em teste de ortostatismo passivo. O TTr incluiu 9 sessões hospitalares (3x/semana, 30 minutos) com monitorizac¸ão contínua de pressão arterial e frequência cardíaca (60◦ - 6 sessões - 70◦ - 3 sessões), complementadas com treino diário no domicílio e elevação da cabeceira a 10◦ durante o sono. O volume sistólico, o débito cardíaco, a resistência vascular periférica, a sensibilidade do barorreflexo e a variabilidade da frequência cardíaca foram calculados. Todos os doentes foram reavaliados no fim do 1.◦ mês e no final de cada 6 meses num período máximo de 36 meses (follow-up 24±12 meses). Resultados: Ao longo das sessões de TTr verificou-se um aumento significativo e consistente da resistência total periférica (1485±225 vs. 1591±187 dyne*s/cm−5, p < 0,05) associado a uma diminuição do seu desvio-padrão (206±60 vs. 150±42, p < 0,05). Durante o período de follow-up, houve recorrência de síncope em 5D (19%), com redução significativa do número de síncopes (4,0±3,2/D nos 12 meses pre-TTr vs. 1,4±0,8/D pos-TTr, p < 0,05). Conclusão: Em doentes com SNc refratária, o TTr mostrou ser uma opção terapêutica eficaz, com benefício a longo prazo. A melhor tolerância ao ortostatismo parece resultar do aumento da reserva vasoconstritora e da sua menor variabilidade
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