Whole Slide Image Cytometry: a Novel Method for the Detection and Quantification of Abnormal DNA Contents in Barrett’s Oesophagus

Background: Barrett's oesophagus (BO) is a well recognized precursor of the majority of cases of oesophageal adenocarcinoma (OAC). Endoscopic surveillance of BO patients is frequently undertaken in an attempt to detect early OAC, high grade dysplasia (HGD) or low grade dysplasia (LGD). However histological interpretation and grading of dysplasia is subjective and poorly reproducible. The alternative flow cytometry and cytology-preparation image cytometry techniques require large amounts of tissue and specialist expertise which are not widely available for frontline health care.
Methods: This study has combined whole slide imaging with DNA image cytometry, to provide a novel method for the detection and quantification of abnormal DNA contents. 20 cases were evaluated, including 8 Barrett's specialised intestinal metaplasia (SIM), 6 LGD and 6 HGD. Feulgen stained oesophageal sections (1µm thickness) were digitally scanned in their entirety and evaluated to select regions of interests and abnormalities. Barrett’s mucosa was then interactively chosen for automatic nuclei segmentation where irrelevant cell types are ignored. The combined DNA content histogram for all selected image regions was then obtained. In addition, histogram measurements, including 5c exceeding ratio (xER-5C), 2c deviation index (2cDI) and DNA grade of malignancy (DNA-MG), were computed.
Results: The histogram measurements, xER-5C, 2cDI and DNA-MG, were shown to be effective in differentiating SIM from HGD, SIM from LGD, and LGD from HGD. All three measurements discriminated SIM from HGD cases successfully with statistical significance (pxER-5C=0.0041, p2cDI=0.0151 and pDNA-MG=0.0057). Statistical significance is also achieved differentiating SIM from LGD samples with pxER-5C=0.0019, p2cDI=0.0023 and pDNA-MG=0.0030. Furthermore the differences between LGD and HGD cases are statistical significant (pxER-5C=0.0289, p2cDI=0.0486 and pDNA-MG=0.0384).
Conclusion: Whole slide image cytometry is a novel and effective method for the detection and quantification of abnormal DNA content in BO. Compared to manual histological review, this proposed method is more objective and reproducible. Compared to flow cytometry and cytology-preparation image cytometry, the current method is low cost, simple to use and only requires a single 1µm tissue section. Whole slide image cytometry could assist the routine clinical diagnosis of dysplasia in BO, which is relevant for future progression risk to OAC.

"Arqueologias" das aprendizagens em Capelins (Santo António) - Alandroal (1997-2007)

Esta dissertação de mestrado desenvolveu-se no âmbito do projecto “Arqueologia” das Aprendizagens no concelho de Alandroal, que teve, como objectivo primordial, a identificação e caracterização do universo de aprendizagens institucionais disponíveis e concretizadas pela comunidade do território em estudo (Freguesia de Capelins (Santo António) /Alandroal), na década 1997 – 2007. Foram inquiridas, nesta freguesia, 16 instituições e identificadas 30 aprendizagens institucionais, que tiveram maior ocorrência nos anos de 2004, 2005 e 2006. Embora seja uma freguesia essencialmente rural, a área de actividade da maioria das instituições identificadas inscreve-se no sector do comércio por grosso e a retalho e de reparação de veículos automóveis e motociclos. São, na sua maioria, instituições de natureza privada e reveladoras de organização, no que respeita à sua organização. No entanto, o relacionamento interinstitucional foi pouco dinâmico, existindo um fraco trabalho em rede. Quando existiram parcerias, estas ocorreram extra freguesia e, até mesmo, extra concelho. Seguindo uma análise quantitativa dos dados extraídos da aplicação dos questionários, com recurso a análise estatística, conclui-se que os processos de aprendizagem das instituições inquiridas da freguesia de Capelins apresentam características centradas nas próprias instituições promotoras dessas mesmas aprendizagens, assentes na formação do pessoal, com carácter formal e não formal e relacionaram-se com as áreas de administração pública e defesa, alojamento e restauração e ainda com a área do comércio por grosso e a retalho; ABSTRACT: This dissertation developed under the project "Archaeology" of Learning in the county of Alandroal, which had as its primary objective, the identification and characterization of the universe of available institutional learning and implemented by the community of the area under study (Parish of capelin (San Antonio) / Alandroal), in the decade from 1997 to 2007. Were surveyed in this parish, and 16 institutions identified 30 institutional learning, which have a higher occurrence in the years 2004, 2005 and 2006. Although it is an essentially rural, the parish area of activity of most institutions identified in the sector of wholesale and retail trade and repair of motor vehicles and motorcycles. Are, for the most part, private institutions and revealing of organization, with regard to its organization. However, the interinstitutional relationship was weak and there is a little dynamic networking. When partnered, this extra parish occurred and even extra municipality. Following a quantitative analysis of data taken from the application of questionnaires, using statistical analysis, it is concluded that the learning processes of the institutions surveyed in the parish of Capelins characteristics focused on promoting institutions of those learnings, based on staff training, formal and non-formal nature and related to the areas of public administration and defense, hotels and restaurants and also the area of wholesale and retail trade.