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Glandular tissues form ducts (tubes) and acini (spheres) in multicellular organisms. This process is best demonstrated in the organization of the ductal tree of the mammary gland and in 3D models of morphogenesis in culture. Here, we asked a fundamental question: How do single adult epithelial cells generate polarized acini when placed in a surrogate basement membrane 3D gel? Using human breast epithelial cells from either reduction mammoplasty or nonmalignant breast cell lines, we observed a unique cellular movement where single cells undergo multiple rotations and then maintain it cohesively as they divide to assemble into acini. This coherent angular motion (CAMo) was observed in both primary cells and breast cell lines. If CAMo was disrupted, the final geometry was not a sphere. The malignant counterparts of the human breast cell lines in 3D were randomly motile, did not display CAMo, and did not form spheres. Upon “phenotypic reversion” of malignant cells, both CAMo and spherical architecture were restored. We show that cell-cell adhesion and tissue polarity are essential for the formation of acini and link the functional relevance of CAMo to the establishment of spherical architecture rather than to multicellular aggregation or growth. We propose that CAMo is an integral step in the formation of the tissue architecture and that its disruption is involved in malignant transformation.  相似文献   
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Dissecting intramural hematoma of esophagus (DIHE) is an uncommon entity, characterized by accumulation of blood within the esophageal wall and usually managed conservatively. Only in rare circumstances, DIHE is associated with massive life-threatening hemorrhage requiring emergency treatment. We present a case of DIHE associated with cardiovascular collapse and treated by transcatheter arterial embolization. Transcatheter arterial embolization is a rare treatment option for DIHE associated with hemodynamic instability and only a handful of cases have been reported in the literature.  相似文献   
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New therapeutic options for severe asthma have recently emerged, mostly in the form of monoclonal antibodies (“biologicals”) targeting relevant inflammatory pathways. Currently available agents target different aspects of “Type 2” immunity, and their indications often include overlapping patient groups. We present a round-table discussion that took place during the Annual Meeting of the Respiratory Effectiveness Group (REG), on the reasoning behind the use of different add-on medications for severe asthma, and crucially, on selection strategies. The proposed rational is based on current evidence, including real-life studies, as well as on the appreciation of the relevant complexities. Direct head-to-head comparisons of biologicals are lacking; therefore, algorithms for initial choice and potential switch between agents should be based on understanding the key characteristics of different options and the development of a clear plan with predefined targets and shared decision-making, in a structured way.  相似文献   
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