Magnetic resonance imaging and ultrasound in hepatosplenic schistosomiasis mansoni

We report the findings of abdominal ultrasound and magnetic resonance imaging observed in a patient with advanced schistosomiasis mansoni. A 25-year-old man with hepatosplenic schistosomiasis and variceal bleeding confirmed by upper endoscopy was submitted to abdominal ultrasound and magnetic resonance imaging. During surgery for portal hypertension, a liver biopsy was taken and the diagnosis of Symmers' fibrosis was confirmed. magnetic resonance imaging scans gave more precise information about the gallbladder, periportal thickening and abdominal venous system than did the ultrasound.

The contribution of R��mulo de Carvalho to Portuguese science education (1934-1974): a humanistic project?

Submitted in accordance with the requirements for the degree of Doctor of Philosophy (Doutoramento em co-tutela)The University of Leeds School of Education

Staging the Scientist: The Representation of Science and its Processes in American and British Drama

Disserta����o apresentada para cumprimento dos requisitos necess��rios �� obten����o do grau de Mestre em Estudos Ingleses e Norte Americanos

Nitrogen (N) : from science to society. A science communication project

O Azoto (N): da ci��ncia para a sociedade �� um projecto de comunica����o de ci��ncia que tem por objecNvo consciencializar os jovens para as amea��as que o azoto (N) em excesso traz para a humanidade. Pode ser dividido em duas partes. Uma, de invesNga����o, sobre a an��lise de resultados de uma consulta p��blica realizada entre professores, usando o m��todo qualitaNvo do focus group, para compreender a sua sensibilidade e propostas de solu����o para minimizar o excesso de N no ambiente. Os resultados obNdos foram instrumentais para o desenvolvimento da segunda parte. Esta segunda parte �� uma proposta de projecto a submeter ao Horizon 2020, no ��m-����� bito da ���Science with and for Society ���. Nela se prop��e uma abordagem educaNva trans-�����disciplinar, conseguida atrav��s da interac����o entre docentes do secund��rio, e do ensino superior, associa����o de pais e organiza����es c��vicas n��o governamentais, com vista �� consciencializa����o dos jovens para as amea��as do N em excesso no meio ambiente, fazendo o enquadramento cien@fico e fornecendo abordagens tecnol��gi-����� cas. A inova����o desta proposta baseia-�����se: (i) no acompanhamento e desenvolvimen-����� to profissional dos docentes do secund��rio, (ii) na moNva����o dos estudantes a de-����� senvolver o seu pr��prio estudo e pesquisa com a tutoria dos docentes, da escola e do ensino superior, e (iii) no desenvolvimento de capacidades de comunica����o dos jo-����� vens para exercer uma cidadania acNva em prol da minimiza����o das amea��as do N.

Microwave imaging of the axilla to aid breast cancer diagnosis

Breast cancer is the most common type of cancer among women all over the world. An important issue that is not commonly addressed in breast cancer imaging literature is the importance of imaging the underarm region���where up to 80% of breast cancer cells can metastasise to. The first axillary lymph nodes to receive drainage from the primary tumour in the breast are called Sentinel Node. If cancer cells are found in the Sentinel Node, there is an increased risk of metastatic breast cancer which makes this evaluation crucial to decide what follow-up exams and therapy to follow. However, non-invasive detection of cancer cells in the lymph nodes is often inconclusive, leading to the surgical removal of too many nodes which causes adverse side-effects for patients. Microwave Imaging is one of the most promising non-invasive imaging modalities for breast cancer early screening and monitoring. This novel study tests the feasibility of imaging the axilla region by means of the simulation of an Ultra-Wideband Microwave Imaging system. Simulations of such system are completed in several 2D underarm models that mimic the axilla. Initial imaging results are obtained by means of processing the simulated backscattered signals by eliminating artefacts caused by the skin and beamforming the processed signals in order to time-align all the signals recorded at each antenna. In this dissertation several image formation algorithms are implemented and compared by visual inspection of the resulting images and through a range of performance metrics, such as Signal-to-Clutter Ratio and FullWidth Half Maximum calculations. The results in this study showed that Microwave Imaging is a promising technique that might allow to identify the presence and location of metastasised cancer cells in axillary lymph nodes, enabling the non-invasive evaluation of breast cancer staging.

Diffusional kurtosis imaging using a fast heuristic constrained linear least squares algorithm: a plugin for OsiriX

Diffusion Kurtosis Imaging (DKI) is a fairly new magnetic resonance imag-ing (MRI) technique that tackles the non-gaussian motion of water in biological tissues by taking into account the restrictions imposed by tissue microstructure, which are not considered in Diffusion Tensor Imaging (DTI), where the water diffusion is considered purely gaussian. As a result DKI provides more accurate information on biological structures and is able to detect important abnormalities which are not visible in standard DTI analysis. This work regards the development of a tool for DKI computation to be implemented as an OsiriX plugin. Thus, as OsiriX runs under Mac OS X, the pro-gram is written in Objective-C and also makes use of Apple���s Cocoa framework. The whole program is developed in the Xcode integrated development environ-ment (IDE). The plugin implements a fast heuristic constrained linear least squares al-gorithm (CLLS-H) for estimating the diffusion and kurtosis tensors, and offers the user the possibility to choose which maps are to be generated for not only standard DTI quantities such as Mean Diffusion (MD), Radial Diffusion (RD), Axial Diffusion (AD) and Fractional Anisotropy (FA), but also DKI metrics, Mean Kurtosis (MK), Radial Kurtosis (RK) and Axial Kurtosis (AK).The plugin was subjected to both a qualitative and a semi-quantitative analysis which yielded convincing results. A more accurate validation pro-cess is still being developed, after which, and with some few minor adjust-ments the plugin shall become a valid option for DKI computation

Divulgar ci��ncia para diferentes p��blicos. Uma experi��ncia no projeto STOL - Science Through Our Lives

O est��gio que aqui se relata enquadra-se no ��mbito do mestrado em Comunica����o de Ci��ncia, da Faculdade de Ci��ncias Sociais Humanas (FCSH) da Universidade Nova de Lisboa (UNL) e do Instituto de Tecnologia Qu��mica e Biol��gica (ITQB). Foi realizado no projeto STOL ��� Science Through Our Lives, do Centro de Biologia Molecular e Ambiental (CBMA) da Escola de Ci��ncias da Universidade do Minho (ECUM), e teve a dura����o de tr��s meses. Esta componente pr��tica do mestrado permitiu desenvolver um trabalho in loco, com o objetivo de servir, sobretudo, a comunica����o de ci��ncia informal. As principais atividades desenvolvidas foram exposi����es (Homo numericus; ���Ponto a Ponto Enche a Ci��ncia o Espa��o), produ����o de materiais educativos (Objetos Educativos para a Casa das Ci��ncias), campanhas de sensibiliza����o (Comemora����o do Dia Mundial da ��gua), ausculta����o do p��blico (Vox Pop), cr��nicas de jornal (coluna ���Aqui h�� Ci��ncia���) e estabelecimento de parcerias estrat��gicas entre o STOL e outras for��as vivas da regi��o (AVianense e ���Di��rio do Minho���). Ao integrar as atividades a decorrer no projeto STOL, foi poss��vel contribuir com sugest��es e novos materiais, e implementar projetos cujo principal objetivo foi o contacto direto com o p��blico. De todo o trabalho se obteve um feedback positivo, conforme se documenta neste relat��rio e respetivos anexos. Se alguns constrangimentos podem ser enunciados (falta de recursos econ��micos e humanos, fraca tradi����o de envolvimento da popula����o com a ci��ncia e vice-versa, e a consider��vel falta de apoio institucional a atividades de divulga����o de ci��ncia), tamb��m devem ser evidenciados aspetos muito positivos como a din��mica do grupo STOL, a capacidade de envolver diferentes p��blicos nas suas atividades, diferenciar estrat��gias para esses grupos, e finalmente, avaliar, sempre que poss��vel, o seu desempenho, incluindo os resultados nas atividades seguintes. Neste contexto foram aplicados os conhecimentos adquiridos durante o primeiro ano curricular do mestrado, permitindo o ganho de experi��ncia na ��rea de trabalho onde a autora se sente realizada e pretende permanecer.

How effective is dog culling in controlling zoonotic visceral leishmaniasis? a critical evaluation of the science, politics and ethics behind this public health policy

INTRODUCTION: Zoonotic kala-azar, a lethal disease caused by protozoa of the genus Leishmania is considered out of control in parts of the world, particularly in Brazil, where transmission has spread to cities throughout most of the territory and mortality presents an increasing trend. Although a highly debatable measure, the Brazilian government regularly culls seropositive dogs to control the disease. Since control is failing, critical analysis concerning the actions focused on the canine reservoir was conducted. METHODS: In a review of the literature, a historical perspective focusing mainly on comparisons between the successful Chinese and Soviet strategies and the Brazilian approach is presented. In addition, analyses of the principal studies regarding the role of dogs as risk factors to humans and of the main intervention studies regarding the efficacy of the dog killing strategy were undertaken. Brazilian political reaction to a recently published systematic review that concluded that the dog culling program lacked efficiency and its effect on public policy were also reviewed. RESULTS: No firm evidence of the risk conferred by the presence of dogs to humans was verified; on the contrary, a lack of scientific support for the policy of killing dogs was confirmed. A bias for distorting scientific data towards maintaining the policy of culling animals was observed. CONCLUSIONS: Since there is no evidence that dog culling diminishes visceral leishmaniasis transmission, it should be abandoned as a control measure. Ethical considerations have been raised regarding distorting scientific results and the killing of animals despite minimal or absent scientific evidence

Ultrasound and magnetic resonance imaging findings in Schistosomiasis mansoni: expanded gallbladder fossa and fatty hilum signs

INTRODUCTION: There is no study relating magnetic resonance imaging (MRI) to ultrasound (US) findings in patients with Schistosomiasis mansoni. Our aim was to describe MRI findings inpatients with schistosomal liver disease identified by US. METHODS: Fifty-four patients (mean age 41.6��13.5years) from an area endemic for Schistosomiasis mansoni were selected for this study.All had US indicating liver schistosomal fibrosis and were evaluated with MRI performed witha 1.5-T superconducting magnet unit (Sigma). RESULTS: Forty-seven (87%) of the 54 patientsshowing signs of periportal fibrosis identified through US investigation had confirmed diagnosesby MRI. In the seven discordant cases (13%), MRI revealed fat tissue filling in the hilar periportalspace where US indicated isolated thickening around the main portal vein at its point of entryto the liver. We named this the fatty hilum sign. One of the 47 patients with MRI evidence ofperiportal fibrosis had had his gallbladder removed previously. Thirty-five (76.1%) of the other46 patients had an expanded gallbladder fossa filled with fat tissue, whereas MRI of the remainingeleven showed pericholecystic signs of fibrosis. CONCLUSIONS: Echogenic thickening of thegallbladder wall and of the main portal vein wall heretofore attributed to fibrosis were frequentlyidentified as fat tissue in MRI. However, the gallbladder wall thickening shown in US (expandedgallbladder fossa in MRI) is probably secondary to combined hepatic morphologic changes inschistosomiasis, representing severe liver involvement.

Soap bubble appearance in brain magnetic resonance imaging: cryptococcal meningoencephalitis

Although cryptococcal infections begin in the lungs, meningoencephalitis is the most frequently encountered manifestation of cryptococcosis among individuals with advanced immunosuppression. As the infection progresses along the Virchow-Robin spaces, these structures may become dilated with mucoid material produced by the capsule of the organism. We report a case of a 24-year-old man with cryptococcal meningoencephalitis in which magnetic resonance imaging showed clusters of gelatinous pseudocysts in the periventricular white matter, basal ganglia, mammillary bodies, midbrain peduncles and nucleus dentatus with a soap bubble appearance.

Structural connectivity based on diffusion Kurtosis imaging

Structural connectivity models based on Diffusion Tensor Imaging (DTI) are strongly affected by the technique���s inability to resolve crossing fibres, either intra- or inter-hemispherical connections. Several models have been proposed to address this issue, including an algorithm aiming to resolve crossing fibres which is based on Diffusion Kurtosis Imaging (DKI). This technique is clinically feasible, even when multi-band acquisitions are not available, and compatible with multi-shell acquisition schemes. DKI is an extension of DTI enabling the estimation of diffusion tensor and diffusion kurtosis metrics. In this study we compare the performance of DKI and DTI in performing structural brain connectivity. Six healthy subjects were recruited, aged between 25 and 35 (three females). The MRI experiments were performed using a 3T Siemens Trio with a 32-channel head coil. The scans included a T1-weighted sequence (1mm3), and a DWI with b-values 0, 1000 and 2000 s:mm

Vascular lesions of the lumbar epidural space: magnetic resonance imaging features of epidural cavernous hemangioma and epidural hematoma

The authors report the magnetic resonance imaging diagnostic features in two cases with respectively lumbar epidural hematoma and cavernous hemangioma of the lumbar epidural space. Enhanced MRI T1-weighted scans show a hyperintense signal rim surrounding the vascular lesion. Non-enhanced T2-weighted scans showed hyperintense signal.