Sensitivity correction of images obtained with the prototype Clear-PEM in pre-clinical environment

Dissertation presented at Faculdade de Ciências e Tecnologia Universidade Nova de Lisboa to obtain a Master Degree in Biomedical EngineeringNuclear medicine has, when compared to anatomical imaging techniques, the great advantage of identifying the metabolic activity of the cells, hence becoming a great option for tumour identification. A new technology in this area is Positron Emission Mammography (PEM) that follows the same physical basics of Positron Emission Tomography (PET). The Clear-PEM project, a Portuguese research project, uses this technology and, in alternative to the whole-body exam, only the breast is examined, using two detector plates that rotate around the breast to detect radiation. The prototype has the ability to perform a complementary exam of the axillary region. This scanner is designed to detect small lesions or tumours in early stages, with high resolution and high sensitivity. After the acquisition, the data undergoes a process of reconstruction and corrections. It is our job to study which parameters should be adjusted in order to get the best contrast between lesions and the breast background, as well as meeting the high resolution standards we set to achieve. This work consisted in the correction of some characteristics that might influence image quality. The first correction made was the elimination of the presence of the gaps between the detector crystals’ effects, resulting in the enhancement of the image Signal-to-Noise Ratio (SNR). By varying the energy window of the image acquisitions, it was possible to minimize the effect of scattered photons, and varying the timing window minimized the effect of random coincidences

Dental and composite resin discoloration induced by different hydraulic calcium silicate-based cements: two-year in vitro assessment

Few long-term studies assess the discoloration induced by hydraulic calcium silicate-based cement on dental structures. In addition, as far as we know, no long-term study has assessed the discoloration induced by these cement on composite resin. Objective: This in vitro study aimed to assess, during a period of two years, the discoloration potential of different hydraulic calcium silicate-based cements (hCSCs) on the enamel/dentin structure and composite resin restoration. Methodology: A total of 40 enamel/dentin discs were obtained from bovine incisors, and 40 composite resin discs (10 mm in diameter × 2 mm thick) were fabricated. A 0.8 mm-deep cavity was made in the center of each disc and filled with the following hCSCs (n=10): Original MTA (Angelus); MTA Repair HP (Angelus); NeoMTA Plus (Avalon); and Biodentine (Septodont). An initial color measurement was performed (T0 - baseline). After 7, 15, 30, 45, 90, 300 days, and two years, new color measurements were performed to determine the color (ΔE00), lightness (ΔL’), chroma (ΔC’), hue differences (ΔH’), and whiteness index (WID). Results: For enamel/dentin, the ΔE00 was significant among groups and periods (p<0.05). NeoMTA Plus had the greatest ΔE00. The NeoMTA Plus group had the greatest ΔE00 after two years for composite resin. Significant reduction in lightness was observed for all groups after two years (p<0.05). The most significant WID values were observed after 30 days for Biodentine (enamel/dentin) and MTA Repair HP groups (composite resin) (p<0.05). Conclusions: The hCSCs changed the colorimetric behavior of both substrates, leading to greater darkening over time. The Bi2O3 in the Original MTA seems relevant in the short periods of color change assessment

Morphological and Postural changes in the foot during pregnancy and puerperium : a longitudinal study

The aim of this study is to observe the morphological and postural changes to the foot that take place during pregnancy and the puerperium. Method: In this descriptive, observational, longitudinal study, we analysed 23 pregnant women, with particular attention to morphological and postural aspects of the foot, at three time points during and after pregnancy: in weeks 9-13 of gestation, weeks 32-35 of gestation and weeks 4-6 after delivery. The parameters considered were changes in foot length, the Foot Posture Index (FPI) and the Hernández Corvo Index, which were analysed using a pedigraph and taking into account the Body Mass Index (BMI). The same procedure was conducted in each review. Results: The statistical analyses obtained for each foot did not differ significantly between the three measurement times. A pronator-type footprint was most frequently observed during the third trimester of pregnancy; it was predominantly neutral during the postpartum period. Statistically significant differences between the measurement times were obtained in the right foot for cavus vs. neutral foot type (between the first and third trimesters and also between the first trimester and the puerperium) (in both cases, p < 0.0001). Conclusions: Foot length increases in the third trimester and returns to normal in the puerperium. According to FPI findings, the third trimester of pregnancy is characterised by pronation, while the posture returns to neutrality during the postpartum period. During pregnancy, the plantar arch flattens, and this persists during the puerperium. The incidence of cavus foot increases significantly in the third trimester and in the puerperium

Reuma.pt/vasculitis - the Portuguese vasculitis registry

BACKGROUND: The vasculitides are a group of rare diseases with different manifestations and outcomes. New therapeutic options have led to the need for long-term registries. The Rheumatic Diseases Portuguese Register, Reuma.pt, is a web-based electronic clinical record, created in 2008, which currently includes specific modules for 12 diseases and > 20,000 patients registered from 79 rheumatology centres. On October 2014, a dedicated module for vasculitis was created as part of the European Vasculitis Society collaborative network, enabling prospective collection and central storage of encrypted data from patients with this condition. All Portuguese rheumatology centres were invited to participate. Data regarding demographics, diagnosis, classification criteria, assessment tools, and treatment were collected. We aim to describe the structure of Reuma.pt/vasculitis and characterize the patients registered since its development. RESULTS: A total of 687 patients, with 1945 visits, from 13 centres were registered; mean age was 53.4 ± 19.3 years at last visit and 68.7% were females. The most common diagnoses were Behçet's disease (BD) (42.5%) and giant cell arteritis (GCA) (17.8%). Patients with BD met the International Study Group criteria and the International Criteria for BD in 85.3 and 97.2% of cases, respectively. Within the most common small- and medium-vessel vasculitides registered, median [interquartile range] Birmingham Vasculitis Activity Score (BVAS) at first visit was highest in patients with ANCA-associated vasculitis (AAV) (17.0 [12.0]); there were no differences in the proportion of patients with AAV or polyarteritis nodosa who relapsed (BVAS≥1) or had a major relapse (≥1 major BVAS item) during prospective assessment (p = 1.00, p = 0.479). Biologic treatment was prescribed in 0.8% of patients with GCA, 26.7% of patients with AAV, and 7.6% of patients with BD. There were 34 (4.9%) deaths reported. CONCLUSIONS: Reuma.pt/vasculitis is a bespoke web-based registry adapted for routine care of patients with this form of rare and complex diseases, allowing an efficient data-repository at a national level with the potential to link with other international databases. It facilitates research, trials recruitment, service planning and benchmarking.publishersversionpublishe

USO DE BETABLOQUEADORES NO TRATAMENTO DE HEMANGIOMA INFANTIL

Introduction: Infantile hemangiomas (IHs) are common benign vascular tumors in children. Historical and current treatment options include medical therapy, surgical resection, laser therapy or direct intralesional steroid injections.  Objective: To group the main beta-blockers used in the treatment of infantile hemangioma and address their efficacy and safety. Methodology: Based on all the steps adopted, the guiding question defined was: "Is the use of beta-blockers in patients with infantile hemangioma, when compared to the use of placebo or other drugs, effective in resolving or reducing lesions?". Initially, 220 studies were found. After applying the search criteria, seven articles were chosen to compose the literature review. Results and discussion: it was observed that beta-blockers are widely used in the treatment of IHs, being mainly effective in the early and initial proliferative phases. The most commonly used beta-blocker is propranolol, but in cases of sensitivity or serious adverse events, timolol, atenolol, carteolol and betaxolol can be used, both in topical and oral presentation. Joint therapy with two beta-blockers has also been shown to be effective in resolving His. Conclusion: The use of beta-blockers in the treatment of infantile hemangioma is beneficial to patients, being safe and effective, and presenting little or no systemic side effects.Introducción: Los hemangiomas infantiles (HI) son tumores vasculares benignos frecuentes en niños. Las opciones de tratamiento históricas y actuales incluyen la terapia médica, la resección quirúrgica, la terapia láser o las inyecciones intralesionales directas de esteroides.  Objetivo: Agrupar los principales betabloqueantes utilizados en el tratamiento del hemangioma infantil y abordar su eficacia y seguridad. Metodología: En base a todos los pasos adoptados, la pregunta guía definida fue: "¿Es eficaz el uso de betabloqueantes en pacientes con hemangioma infantil, en comparación con el uso de placebo u otros fármacos, para resolver o reducir las lesiones?". Inicialmente, se encontraron 220 estudios. Tras aplicar los criterios de búsqueda, se eligieron siete artículos para componer la revisión bibliográfica. Resultados y discusión: se observó que los betabloqueantes son ampliamente utilizados en el tratamiento de los HI, siendo principalmente eficaces en las fases proliferativas precoces e iniciales. El betabloqueante más utilizado es el propranolol, pero en casos de sensibilidad o eventos adversos graves, se pueden utilizar timolol, atenolol, carteolol y betaxolol, tanto en presentación tópica como oral. También se ha demostrado que la terapia conjunta con dos betabloqueantes es eficaz para resolver el His. Conclusiones: El uso de betabloqueantes en el tratamiento del hemangioma infantil es beneficioso para los pacientes, siendo seguro y eficaz, y presentando escasos o nulos efectos secundarios sistémicos.Os hemangiomas infantis (HIs) são tumores vasculares benignos comuns em crianças. As opções de tratamento históricas e atuais incluem terapia médica, ressecção cirúrgica, terapia a laser ou injeções intralesionais diretas de esteroides.  Objetivo: agrupar os principais betabloqueadores utilizados no tratamento de hemangioma infantil e abordar sua eficácia e segurança. Metodologia: Com base em todos os passos adotados, a pergunta norteadora definida foi: “O uso de betabloqueadores em pacientes com hemangioma infantil, quando comparado ao uso de placebo ou outras drogas, é eficaz na resolução ou diminuição das lesões?”. Inicialmente, foram encontrados 220 estudos. Após a aplicação dos critérios de busca, foram escolhidos sete artigos para compor a revisão de literatura. Resultados e discussão: observa-se que os betabloqueadores são amplamente utilizados no tratamento de HIs, sendo principalmente eficazes nas fases proliferativa precoce e inicial. O betabloqueador mais utilizado é o propranolol, porém, em casos de sensibilidade ou eventos adversos graves, podem ser utilizados timolol, atenolol, carteolol e betaxolol, tanto em apresentação tópica quanto oral. A terapia conjunta com dois betabloqueadores também se mostrou efetiva na resolução de His. Conclusão: o uso de betabloqueadores no tratamento de hemangioma infantil é benéfico aos pacientes, sendo seguro e efetivo, além de apresentar pouco ou nenhum efeito colateral sistêmico.Os hemangiomas infantis (HIs) são tumores vasculares benignos comuns em crianças. As opções de tratamento históricas e atuais incluem terapia médica, ressecção cirúrgica, terapia a laser ou injeções intralesionais diretas de esteroides.  Objetivo: agrupar os principais betabloqueadores utilizados no tratamento de hemangioma infantil e abordar sua eficácia e segurança. Metodologia: Com base em todos os passos adotados, a pergunta norteadora definida foi: “O uso de betabloqueadores em pacientes com hemangioma infantil, quando comparado ao uso de placebo ou outras drogas, é eficaz na resolução ou diminuição das lesões?”. Inicialmente, foram encontrados 220 estudos. Após a aplicação dos critérios de busca, foram escolhidos sete artigos para compor a revisão de literatura. Resultados e discussão: observa-se que os betabloqueadores são amplamente utilizados no tratamento de HIs, sendo principalmente eficazes nas fases proliferativa precoce e inicial. O betabloqueador mais utilizado é o propranolol, porém, em casos de sensibilidade ou eventos adversos graves, podem ser utilizados timolol, atenolol, carteolol e betaxolol, tanto em apresentação tópica quanto oral. A terapia conjunta com dois betabloqueadores também se mostrou efetiva na resolução de His. Conclusão: o uso de betabloqueadores no tratamento de hemangioma infantil é benéfico aos pacientes, sendo seguro e efetivo, além de apresentar pouco ou nenhum efeito colateral sistêmico

Real-Time PCR in HIV/Trypanosoma cruzi Coinfection with and without Chagas Disease Reactivation: Association with HIV Viral Load and CD4+ Level

Chagas disease is endemic in Latin America and is caused by the flagellate protozoan T. cruzi. The acute phase is asymptomatic in the majority of the cases and rarely causes inflammation of the heart or the central nervous system. Most infected patients progress to a chronic phase, characterized by cardiac or digestive involvement when not asymptomatic. However, when patients are also exposed to an immunosuppressant (such as chemotherapy), neoplasia, or other infections such as HIV, T. cruzi infection may develop into a severe disease (Chagas disease reactivation) involving the heart and central nervous system. The current microscopic methods for diagnosing Chagas disease reactivation are not sensitive enough to prevent the high rate of death observed in these cases. Therefore, we propose a quantitative method to monitor blood levels of the parasite, which will allow therapy to be administered as early as possible, even if the patient has not yet presented symptoms

Health-related quality of life in patients with type 1 diabetes mellitus in the different geographical regions of Brazil : data from the Brazilian Type 1 Diabetes Study Group

Background: In type 1 diabetes mellitus (T1DM) management, enhancing health-related quality of life (HRQoL) is as important as good metabolic control and prevention of secondary complications. This study aims to evaluate possible regional differences in HRQoL, demographic features and clinical characteristics of patients with T1DM in Brazil, a country of continental proportions, as well as investigate which variables could influence the HRQoL of these individuals and contribute to these regional disparities. Methods: This was a retrospective, cross-sectional, multicenter study performed by the Brazilian Type 1 Diabetes Study Group (BrazDiab1SG), by analyzing EuroQol scores from 3005 participants with T1DM, in 28 public clinics, among all geographical regions of Brazil. Data on demography, economic status, chronic complications, glycemic control and lipid profile were also collected. Results: We have found that the North-Northeast region presents a higher index in the assessment of the overall health status (EQ-VAS) compared to the Southeast (74.6 ± 30 and 70.4 ± 19, respectively; p < 0.05). In addition, North- Northeast presented a lower frequency of self-reported anxiety-depression compared to all regions of the country (North-Northeast: 1.53 ± 0.6; Southeast: 1.65 ± 0.7; South: 1.72 ± 0.7; Midwest: 1.67 ± 0.7; p < 0.05). These findings could not be entirely explained by the HbA1c levels or the other variables examined. Conclusions: Our study points to the existence of additional factors not yet evaluated that could be determinant in the HRQoL of people with T1DM and contribute to these regional disparities

Práticas artísticas no ensino básico e secundário

Sobre a Matéria-Prima, há novidades e perigos. O tempo vivido na Europa e no contexto global tem vindo a acentuar a urgência das prioridades quantificadas, com um discurso dominante onde há menos política (pessoas) e mais representação económica (coisas). O correlato entre pessoas e coisas é, como sabemos, o dinheiro, ou trabalho reificado. A crise europeia, em torno da dívida soberana e dos maiores orçamentos do mundo, da capacidade da sua gestão na linguagem dura dos mercados e das taxas de juro veio modificar os objetivos imediatos da Europa, que em 2000 eram ambiciosos — “a sociedade mais competitiva do mundo em 2010” — para uma estratégia de emergência, agora chamada horizonte 2020. Este é o panorama ideal para colocar o ensino artístico em risco. Os fóruns internacionais passaram a valorizar os resultados da educação em rankings e sondagens de aproveitamento, cuja principal estratégia e preocupação é a mensurabilidade e comparabilidade, como são exemplo os relatórios PISA: avaliam-se em todos os países, as competências em Ciências, Matemática e Língua Materna. A matéria-prima de amanhã corre riscos de desaparecer gradualmente, pelos cortes de carga horária, pela concepção extracurricular da educação artística, pela sua perceção menorizada em função das concepções competitivas da sociedade contemporânea globalizada.info:eu-repo/semantics/publishedVersio