15 research outputs found

    Increased peri-ductal collagen micro-organization may contribute to raised mammographic density

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    BACKGROUND: High mammographic density is a therapeutically modifiable risk factor for breast cancer. Although mammographic density is correlated with the relative abundance of collagen-rich fibroglandular tissue, the causative mechanisms, associated structural remodelling and mechanical consequences remain poorly defined. In this study we have developed a new collaborative bedside-to-bench workflow to determine the relationship between mammographic density, collagen abundance and alignment, tissue stiffness and the expression of extracellular matrix organising proteins. METHODS: Mammographic density was assessed in 22 post-menopausal women (aged 54–66 y). A radiologist and a pathologist identified and excised regions of elevated non-cancerous X-ray density prior to laboratory characterization. Collagen abundance was determined by both Masson’s trichrome and Picrosirius red staining (which enhances collagen birefringence when viewed under polarised light). The structural specificity of these collagen visualisation methods was determined by comparing the relative birefringence and ultrastructure (visualised by atomic force microscopy) of unaligned collagen I fibrils in reconstituted gels with the highly aligned collagen fibrils in rat tail tendon. Localised collagen fibril organisation and stiffness was also evaluated in tissue sections by atomic force microscopy/spectroscopy and the abundance of key extracellular proteins was assessed using mass spectrometry. RESULTS: Mammographic density was positively correlated with the abundance of aligned periductal fibrils rather than with the abundance of amorphous collagen. Compared with matched tissue resected from the breasts of low mammographic density patients, the highly birefringent tissue in mammographically dense breasts was both significantly stiffer and characterised by large (>80 μm long) fibrillar collagen bundles. Subsequent proteomic analyses not only confirmed the absence of collagen fibrosis in high mammographic density tissue, but additionally identified the up-regulation of periostin and collagen XVI (regulators of collagen fibril structure and architecture) as potential mediators of localised mechanical stiffness. CONCLUSIONS: These preliminary data suggest that remodelling, and hence stiffening, of the existing stromal collagen microarchitecture promotes high mammographic density within the breast. In turn, this aberrant mechanical environment may trigger neoplasia-associated mechanotransduction pathways within the epithelial cell population. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13058-015-0664-2) contains supplementary material, which is available to authorized users

    Environmental challenges in Nigeria’s Delta Region and Agriculture

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    The paper discussed the environmental challenges in the Niger-Delta region of Nigeria with emphasis on the impacts on agricultural production. It thus discussed the concepts of Niger-Delta, Environmental pollution, Niger-Delta crises and Agriculture. The paper posits that there are positive relationships between these concepts justified on the basis of socio-Economic, political, health and agricultural under-development. The paper hence sees a looming bleak and dead-end to agricultural production and food security in Niger-Delta. Based on these theoretical positions, it recommends for active and pro-active measures to the environmental challenges in Niger-Delta region of Nigeria

    Instructional Variables and Students’ Acquisition of Employable Vocational Skills From Technical Colleges in Akwa Ibom State, Nigeria

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    This study focused on the impact of teacher quality, teaching methods, and access to training materials on students’ acquisition of employable skills in vocational technical subjects, for self employment in Akwa Ibom State, Nigeria. Three questions and three hypotheses were formulated and tested in the study. The population of the study comprised 240 senior technical II students in the six technical colleges in the state. A random sampling technique was used to obtain a sample size of 120 students for the study. A 28 - item structured questionnaire titled, Students’ Acquisition of Employable Skills Questionnaire (SAESQ) with a four-point rating response options were used for data collection. Mean, Pearson Product Moment Correlation (PPMC) and Regressional analysis were used for data analysis. The results indicated significant relationships between teacher quality, teaching methods and students’ acquisition of employable skills. We recommend the provision of modern workshop equipment and employment of qualified and experienced teachers for effective teaching/training of students of vocational and technical education in Akwa Ibom State
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