reduced models for blood flow in curved vessels

Flow in curved pipes has been intensively investigated and applications to arterial o w are relevant both in physiological and pathological conditions. A comprehensive survey of the work devel- oped over almost one century from experimental and modelling point of view is carried out. Despite its complex nature, the 3D curved o w can be modeled, under reasonable assumptions, accounting only for 2, or even 1, geometrical dimensions. A couple of dieren t reduced models are presented and discussed here. Results of numerical simulations demonstrate the role of curvature in the formation of the secondary o w patterns and in the asymmetry of wall shear stresses. Both the above features can have important haemodynamical eects and clinical diagnostic velocimeters should be equipped with correction algorithms for the measurement bias induced by vessel curvature

A redução ao sistema como operação epistêmica na pesquisa descritiva e explicativa em ciência da informação

The scientific reduction to the individual or atom, typical of analytical, disciplinary science, earned the derogatory designation “reductionism” to denounce its inadequacy to deal with concrete, complex problems. Bunge's systemism is a worldview at variance with reductionism, but also with the “reduction to the whole” of holistic approaches that deny the possibility of explanation through analysis. This article presents the reduction to the system, a fundamental epistemic operation of systemism, with emphasis on its application to information science. We discuss the fundamentals of systemism, particularly its composition-environment-structure-mechanism, or CESM model, which frames systemist reduction. A graduate course on systemist research with CESM is presented, including a new modeling method, illustrated with students' models. We show how to explain systemic effects, even if counterintuitive, claiming that systemist research is in better conditions to do so than its rivals reductionism and holism

A redução ao sistema como operação epistêmica na pesquisa descritiva e explicativa em ciência da informação

The scientific reduction to the individual or atom, typical of analytical, disciplinary science, earned the derogatory designation “reductionism” to denounce its inadequacy to deal with concrete, complex problems. Bunge's systemism is a worldview at variance with reductionism, but also with the “reduction to the whole” of holistic approaches that deny the possibility of explanation through analysis. This article presents the reduction to the system, a fundamental epistemic operation of systemism, with emphasis on its application to information science. We discuss the fundamentals of systemism, particularly its composition-environment-structure-mechanism, or CESM model, which frames systemist reduction. A graduate course on systemist research with CESM is presented, including a new modeling method, illustrated with students' models. We show how to explain systemic effects, even if counterintuitive, claiming that systemist research is in better conditions to do so than its rivals reductionism and holism

A redução ao sistema como operação epistêmica na pesquisa descritiva e explicativa em ciência da informação

The scientific reduction to the individual or atom, typical of analytical, disciplinary science, earned the derogatory designation “reductionism” to denounce its inadequacy to deal with concrete, complex problems. Bunge's systemism is a worldview at variance with reductionism, but also with the “reduction to the whole” of holistic approaches that deny the possibility of explanation through analysis. This article presents the reduction to the system, a fundamental epistemic operation of systemism, with emphasis on its application to information science. We discuss the fundamentals of systemism, particularly its composition-environment-structure-mechanism, or CESM model, which frames systemist reduction. A graduate course on systemist research with CESM is presented, including a new modeling method, illustrated with students' models. We show how to explain systemic effects, even if counterintuitive, claiming that systemist research is in better conditions to do so than its rivals reductionism and holism

Decreased Autocrine EGFR Signaling in Metastatic Breast Cancer Cells Inhibits Tumor Growth in Bone and Mammary Fat Pad

Breast cancer metastasis to bone triggers a vicious cycle of tumor growth linked to osteolysis. Breast cancer cells and osteoblasts express the epidermal growth factor receptor (EGFR) and produce ErbB family ligands, suggesting participation of these growth factors in autocrine and paracrine signaling within the bone microenvironment. EGFR ligand expression was profiled in the bone metastatic MDA-MB-231 cells (MDA-231), and agonist-induced signaling was examined in both breast cancer and osteoblast-like cells. Both paracrine and autocrine EGFR signaling were inhibited with a neutralizing amphiregulin antibody, PAR34, whereas shRNA to the EGFR was used to specifically block autocrine signaling in MDA-231 cells. The impact of these was evaluated with proliferation, migration and gene expression assays. Breast cancer metastasis to bone was modeled in female athymic nude mice with intratibial inoculation of MDA-231 cells, and cancer cell-bone marrow co-cultures. EGFR knockdown, but not PAR34 treatment, decreased osteoclasts formed in vitro (p<0.01), reduced osteolytic lesion tumor volume (p<0.01), increased survivorship in vivo (p<0.001), and resulted in decreased MDA-231 growth in the fat pad (p<0.01). Fat pad shEGFR-MDA-231 tumors produced in nude mice had increased necrotic areas and decreased CD31-positive vasculature. shEGFR-MDA-231 cells also produced decreased levels of the proangiogenic molecules macrophage colony stimulating factor-1 (MCSF-1) and matrix metalloproteinase 9 (MMP9), both of which were decreased by EGFR inhibitors in a panel of EGFR-positive breast cancer cells. Thus, inhibiting autocrine EGFR signaling in breast cancer cells may provide a means for reducing paracrine factor production that facilitates microenvironment support in the bone and mammary gland

Super Resolution Microscopy Reveals that Caveolin-1 Is Required for Spatial Organization of CRFB1 and Subsequent Antiviral Signaling in Zebrafish

10.1371/journal.pone.0068759PLoS ONE87-POLN