Assessing the Permeability of Engineered Capillary Networks in a 3D Culture

Many pathologies are characterized by poor blood vessel growth and reduced nutrient delivery to the surrounding tissue, introducing a need for tissue engineered blood vessels. Our lab has developed a 3D co-culture method to grow interconnected networks of pericyte-invested capillaries, which can anastamose with host vasculature following implantation to restore blood flow to ischemic tissues. However, if the engineered vessels contain endothelial cells (ECs) that are misaligned or contain wide junctional gaps, they may function improperly and behave more like the pathologic vessels that nourish tumors. The purpose of this study was to test the resistance to permeability of these networks in vitro, grown with different stromal cell types, as a metric of vessel functionality. A fluorescent dextran tracer was used to visualize transport across the endothelium and the pixel intensity was quantified using a customized MATLAB algorithm. In fibroblast-EC co-cultures, the dextran tracer easily penetrated through the vessel wall and permeability was high through the first 5 days of culture, indicative of vessel immaturity. Beyond day 5, dextran accumulated at the periphery of the vessel, with very little transported across the endothelium. Quantitatively, permeability dropped from initial levels of 61% to 39% after 7 days, and to 7% after 2 weeks. When ECs were co-cultured with bone marrow-derived mesenchymal stem cells (MSCs) or adipose-derived stem cells (AdSCs), much tighter control of permeability was achieved. Relative to the EC-fibroblast co-cultures, permeabilities were reduced 41% for the EC-MSC co-cultures and 50% for the EC-AdSC co-cultures after 3 days of culture. By day 14, these permeabilities decreased by 68% and 77% over the EC-fibroblast cultures. Co-cultures containing stem cells exhibit elevated VE-cadherin levels and more prominent EC-EC junctional complexes when compared to cultures containing fibroblasts. These data suggest the stromal cell identity influences the functionality and physiologic relevance of engineered capillary networks

Rotation sensing based on the symmetry properties of an open-ended microstrip line loaded with a split ring resonator

This paper proposes the principle for rotation sensing based on an open-ended microstrip line loaded with a split ring resonator (SRR). It is shown that the variations in the depth of the resonance notch in the reflection coefficient of the structure can be used to sense the rotation angle of the SRR. This effect arises from the rotation-induced break of symmetry for the geometry. The proposed sensor benefits from a compact size and a higher dynamic range compared to previously published rotation sensors based on depth of notch. The sensor also benefits from immunity to the environmental changes such as temperature variations.Zahra Shaterian, Ali K. Horestani, and Christophe Fumeau

Metamaterial-inspired displacement sensor with high dynamic range

Proceedings of the 4th International Conference on Metamaterials, Photonic Crystals and Plasmonics, META 2013, United Arab Emirates, 18 Mar - 22 Mar 201: pp.274-276http://www.ieee.org/conferences_events/conferences/conferencedetails/index.html?Conf_ID=3070

Single and dual band-notched ultra-wideband antenna based on dumbbell-shaped defects and complementary split ring resonators

Printed ultra-wideband (UWB) monopole antennas are proposed with compact size and single/dual band-notched characteristics to prevent interference with nearby communication systems. It is shown that a dumbbell-shaped defect in the radiating element of a UWB monopole antenna can produce a notch band. The frequency of the notch can be easily adjusted by changing the physical dimensions of the defected structure. It is further shown that, a pair of complementary split ring resonators (CSRRs) embedded in the dumbbell-shaped defect can be used to produce a second notch. The proposed dual bandnotched antenna can be used for the rejection of interference withWorldwide Interoperability for Microwave Access (WiMAX) systems covering the 3.3-3.6 GHz band, and either lower or upper wireless local area networks (WLANs) operating in the 5.15-5.35 GHz and 5.725-5.825 GHz bands, respectively.Ali K. Horestani, Zahra Shaterian, Thomas Kaufmann, and Christophe Fumeau

QUALITY OF LIFE IN PATIENTS HOSPITALIZED WITH HEART FAILURE: A NOVEL TWO QUESTIONNAIRE STUDY

Heart failure (HF) is a common disease with high health care costs and high mortality rate Knowledge of the health-related quality of life (QOL) outcomes of HF may guide decision making and be useful in assessing new therapies for population. Yet little is known about QOL of HF patients in Iran. Objectives: To assess health related QOL of patients with HF with two different instrument and to correlate these two measures and to assess the role of relevant factors. Analytic cross sectional study was conducted involving 230 adult patients hospitalized with HF, demographic data and health -related quality of life were determined by interview; for assessing of quality of life was used SF-36 and Minnesota questionnaires. Simple random sampling from ward patients list choose patients. Patients had no other man diseases that affected their quality of life. Results: 118 female (53.3%) and 112 male (48.7%) with mean age of 51.4 +/-13.18 were collected. 61 patients (26.5%) were smoker and 100 patients (43.5%) had positive familial hearth disease history. Quality of life in some subscale: Physical functioning, Role physical and vitality, and Minnesota scare affected from patients age. Male patients had better quality of life than female in Minnesota scale and physical functioning, body pain, general health, vitality and emotional well-being. Duration of diagnosis affected Minnesota scale and role physical. Positive familial heart disease history affected physical functioning. Iranian patients have worse quality of life than other patients. This shows patients age, sex, duration of diagnosis, smoking and positive familial hearth disease history affected quality of life in heart failure patients