Paramètres agronomiques liés à la tolérance au sel chez le haricot (Phaseolus vulgaris L.)

Agronomical traits associated with salinity-tolerance in common bean (Phaseolus vulgaris L.). Identifying multiple agronomical parameters associated with salinity-tolerance is important for evaluating common bean (Phaseolus vulgaris L.) cultivars and improving their tolerance to salinity. Six cultivars were grown in soil, under glasshouse conditions and exposed to three salinity levels (control, 25 and 50 mM NaCl) to evaluate their tolerance using their biomass and the relative salt-susceptibility index: I.S.R.S. = D.R.B./I.I.S. (D.R.B.: relative biomass deficit and I.I.S.: salinity intensity index). On the other hand, a comparative field trial was conducted at four experimental stations of INRAT (Ariana, Oued Beja, Oued Meliz and Sejnane) during three consecutive years with sixteen cultivars to determine their grain yield stability, grain size and precocity. Results showed that tolerant cultivars are colour-seeded, early and presented yield stability and medium grain size. By contrast the susceptible cultivars are late, white-seeded and characterized by a less stable yield and small to medium grain size

Socioeconomic Inequalities in Child Malnutrition in Bangladesh: Do They Differ by Region?

Socioeconomic inequality in child malnutrition is well-evident in Bangladesh. However, little is known about whether this inequality differs by regional contexts. We used pooled data from the 2011 and 2014 Bangladesh Demographic and Health Survey to examine regional differences in socioeconomic inequalities in stunting and underweight among children under five. The analysis included 14,602 children aged 0-59 months. We used logistic regression models and the Concentration index to assess and quantify wealth- and education-related inequalities in child malnutrition. We found stunting and underweight to be more concentrated among children from poorer households and born to less-educated mothers. Although the poverty level was low in the eastern regions, socioeconomic inequalities were greater in these regions compared to the western regions. The extent of socioeconomic inequality was the highest in Sylhet and Chittagong for stunting and underweight, respectively, while it was the lowest in Khulna. Regression results demonstrated the protective effects of socioeconomic status (SES) on child malnutrition. The regional differences in the effects of SES tend to diverge at the lower levels of SES, while they converge or attenuate at the highest levels. Our findings have policy implications for developing programs and interventions targeted to reduce socioeconomic inequalities in child malnutrition in subnational regions of Bangladesh

Interface modification of clay and graphene platelets reinforced epoxy nanocomposites: a comparative study

The interface between the matrix phase and dispersed phase of a composite plays a critical role in influencing its properties. However, the intricate mecha-nisms of interface are not fully understood, and polymer nanocomposites are no exception. This study compares the fabrication, morphology, and mechanical and thermal properties of epoxy nanocomposites tuned by clay layers (denoted as m-clay) and graphene platelets (denoted as m-GP). It was found that a chemical modification, layer expansion and dispersion of filler within the epoxy matrix resulted in an improved interface between the filler mate-rial and epoxy matrix. This was confirmed by Fourier transform infrared spectroscopy and transmission electron microscope. The enhanced interface led to improved mechanical properties (i.e. stiffness modulus, fracture toughness) and higher glass transition temperatures (Tg) compared with neat epoxy. At 4 wt% m-GP, the critical strain energy release rate G1c of neat epoxy improved by 240 % from 179.1 to 608.6 J/m2 and Tg increased from 93.7 to 106.4 �C. In contrast to m-clay, which at 4 wt%, only improved the G1c by 45 % and Tg by 7.1 %. The higher level of improvement offered by m-GP is attributed to the strong interaction of graphene sheets with epoxy because the covalent bonds between the carbon atoms of graphene sheets are much stronger than silicon-based clay

Antihyperglycemic Activities of Leaves of Three Edible Fruit Plants (Averrhoa carambola, Ficus hispida and Syzygium samarangense) of Bangladesh

Averrhoa carambola L. (Oxalidaceae), Ficus hispida L.f. (Moraceae), and Syzygium samarangense (Blume) Merr. & L.M. Perry (Myrtaceae) are three common plants in Bangladesh, the fruits of which are edible. The leaves and fruits of A. carambola and F. hispida are used by folk medicinal practitioners for treatment of diabetes, while the leaves of S. samarangense are used for treatment of cold, itches, and waist pain. Since scientific studies are absent on the antihyperglycemic effects of the leaves of the three plants, it was the objective of the present study to evaluate the antihyperglycemic potential of methanolic extract of leaves of the plants in oral glucose tolerance tests carried out with glucose-loaded mice. The extracts at different doses were administered one hour prior to glucose administration and blood glucose level was measured after two hours of glucose administration (p.o.) using glucose oxidase method. Significant oral hypoglycemic activity was found with the extracts of leaves of all three plants tested. The fall in serum glucose levels were dose-dependent for every individual plant, being highest at the highest dose tested of 400 mg extract per kg body weight. At this dose, the extracts of A. carambola, F. hispida, and S. samarangense caused, respectively, 34.1, 22.7, and 59.3% reductions in serum glucose levels when compared to control animals. The standard antihyperglycemic drug, glibenclamide, caused a 57.3% reduction in serum glucose levels versus control. Among the three plants evaluated, the methanolic extract of leaves of S. samarangense proved to be the most potent in demonstrating antihyperglycemic effects. The result validates the folk medicinal uses of A. carambola and F. hispida in the treatment of diabetes, and indicates that the leaves of S. samarangense can also possibly be used for amelioration of diabetes-induced hyperglycemia.Key words: Averrhoa carambola, Ficus hispida, Syzygium samarangense, antihyperglycemi

2009 ESC/ERS Pulmonary Hypertension Guidelines and Connective Tissue Disease

ABSTRACTPulmonary hypertension was defined as mean pulmonary artery pressure ≥25 mmHg at the 4th World Symposium on Pulmonary Hypertension. In 2009, the European Society of Cardiology and European Respiratory Society jointly created guidelines for practical pulmonary hypertension classifications and treatments based on the discussions at the 4th World Symposium. This classification is characterized by division into five groups: Pulmonary arterial hypertension (PAH); Pulmonary hypertension due to left heart disease; Pulmonary hypertension due to lung disease and/or hypoxia; Chronic thromboembolic pulmonary hypertension; and Pulmonary hypertension with unclear and/or multifactorial mechanisms.PAH is a common and fatal complication of connective tissue disease (CTD), but pulmonary hypertension in CTD consists of PAH, pulmonary hypertension caused by myocardial involvement, pulmonary veno-occlusive disorder, pulmonary hypertension due to interstitial lung disease. PAH has been studied widely in SSc and the estimated prevalence of 7-12%. Treatment of CTD associated PAH (CTD-PAH) consists of general therapeutic options and specific treatment. Specific treatment of CTD-PAH patients is targeted to produce vasodilatation. Calcium channel blockers (CCBs) are indicated in cases where a sufficient decrease in pulmonary arterial pressure is seen in vasoreactivity testing. If vasoreactivity is absent in CTD-PAH patients, the treatment consists of the endothelin receptor antagonists, the prostacyclin analogues and phosphodiesterase-type 5 inhibitors. Few data are available to support the use of immunosuppression in CTD-PAH. However, some case reports suggested that a minority of CTD-PAH patients could benefit from immunosuppressive therapy. The treatment of CTD-PAH patients may differ from the treatment of idiopathic PAH

Optimizing the lateral beamforming step for filtered-delay multiply and sum beamforming to improve active contour segmentation using ultrafast ultrasound imaging

As an alternative to delay-and-sum beamforming, a novel beamforming technique called filtered-delay multiply and sum (FDMAS) was introduced recently to improve ultrasound B-mode image quality. Although a considerable amount of work has been performed to evaluate FDMAS performance, no study has yet focused on the beamforming step size, , in the lateral direction. Accordingly, the performance of FDMAS was evaluated in this study by fine-tuning to find its optimal value and improve boundary definition when balloon snake active contour (BSAC) segmentation was applied to a B-mode image in ultrafast imaging. To demonstrate the effect of altering in the lateral direction on FDMAS, measurements were performed on point targets, a tissue-mimicking phantom and in vivo carotid artery, by using the ultrasound array research platform II equipped with one 128-element linear array transducer, which was excited by 2-cycle sinusoidal signals. With 9-angle compounding, results showed that the lateral resolution (LR) of the point target was improved by 67.9% and 81.2%, when measured at −6 dB and −20 dB respectively, when was reduced from to . Meanwhile the image contrast ratio (CR) measured on the CIRS phantom was improved by 10.38 dB at the same reduction and the same number of compounding angles. The enhanced FDMAS results with lower side lobes and less clutter noise in the anechoic regions provides a means to improve boundary definition on a B-mode image when BSAC segmentation is applied

From Molecular Signal Activation to Locomotion: An Integrated, Multiscale Analysis of Cell Motility on Defined Matrices

The adhesion, mechanics, and motility of eukaryotic cells are highly sensitive to the ligand density and stiffness of the extracellular matrix (ECM). This relationship bears profound implications for stem cell engineering, tumor invasion and metastasis. Yet, our quantitative understanding of how ECM biophysical properties, mechanotransductive signals, and assembly of contractile and adhesive structures collude to control these cell behaviors remains extremely limited. Here we present a novel multiscale model of cell migration on ECMs of defined biophysical properties that integrates local activation of biochemical signals with adhesion and force generation at the cell-ECM interface. We capture the mechanosensitivity of individual cellular components by dynamically coupling ECM properties to the activation of Rho and Rac GTPases in specific portions of the cell with actomyosin contractility, cell-ECM adhesion bond formation and rupture, and process extension and retraction. We show that our framework is capable of recreating key experimentally-observed features of the relationship between cell migration and ECM biophysical properties. In particular, our model predicts for the first time recently reported transitions from filopodial to “stick-slip” to gliding motility on ECMs of increasing stiffness, previously observed dependences of migration speed on ECM stiffness and ligand density, and high-resolution measurements of mechanosensitive protrusion dynamics during cell motility we newly obtained for this study. It also relates the biphasic dependence of cell migration speed on ECM stiffness to the tendency of the cell to polarize. By enabling the investigation of experimentally-inaccessible microscale relationships between mechanotransductive signaling, adhesion, and motility, our model offers new insight into how these factors interact with one another to produce complex migration patterns across a variety of ECM conditions

Effects of HER2 overexpression on cell signaling networks governing proliferation and migration

Although human epidermal growth factor receptor 2 (HER2) overexpression is implicated in tumor progression for a variety of cancer types, how it dysregulates signaling networks governing cell behavioral functions is poorly understood. To address this problem, we use quantitative mass spectrometry to analyze dynamic effects of HER2 overexpression on phosphotyrosine signaling in human mammary epithelial cells stimulated by epidermal growth factor (EGF) or heregulin (HRG). Data generated from this analysis reveal that EGF stimulation of HER2-overexpressing cells activates multiple signaling pathways to stimulate migration, whereas HRG stimulation of these cells results in amplification of a specific subset of the migration signaling network. Self-organizing map analysis of the phosphoproteomic data set permitted elucidation of network modules differentially regulated in HER2-overexpressing cells in comparison with parental cells for EGF and HRG treatment. Partial least-squares regression analysis of the same data set identified quantitative combinations of signals within the networks that strongly correlate with cell proliferation and migration measured under the same battery of conditions. Combining these modeling approaches enabled association of epidermal growth factor receptor family dimerization to activation of specific phosphorylation sites, which appear to most critically regulate proliferation and/or migration

Inherent Interfacial Mechanical Gradients in 3D Hydrogels Influence Tumor Cell Behaviors

Cells sense and respond to the rigidity of their microenvironment by altering their morphology and migration behavior. To examine this response, hydrogels with a range of moduli or mechanical gradients have been developed. Here, we show that edge effects inherent in hydrogels supported on rigid substrates also influence cell behavior. A Matrigel hydrogel was supported on a rigid glass substrate, an interface which computational techniques revealed to yield relative stiffening close to the rigid substrate support. To explore the influence of these gradients in 3D, hydrogels of varying Matrigel content were synthesized and the morphology, spreading, actin organization, and migration of glioblastoma multiforme (GBM) tumor cells were examined at the lowest (<50 µm) and highest (>500 µm) gel positions. GBMs adopted bipolar morphologies, displayed actin stress fiber formation, and evidenced fast, mesenchymal migration close to the substrate, whereas away from the interface, they adopted more rounded or ellipsoid morphologies, displayed poor actin architecture, and evidenced slow migration with some amoeboid characteristics. Mechanical gradients produced via edge effects could be observed with other hydrogels and substrates and permit observation of responses to multiple mechanical environments in a single hydrogel. Thus, hydrogel-support edge effects could be used to explore mechanosensitivity in a single 3D hydrogel system and should be considered in 3D hydrogel cell culture systems