2,118 research outputs found

    A systems biology analysis of brain microvascular endothelial cell lipotoxicity.

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    BackgroundNeurovascular inflammation is associated with a number of neurological diseases including vascular dementia and Alzheimer's disease, which are increasingly important causes of morbidity and mortality around the world. Lipotoxicity is a metabolic disorder that results from accumulation of lipids, particularly fatty acids, in non-adipose tissue leading to cellular dysfunction, lipid droplet formation, and cell death.ResultsOur studies indicate for the first time that the neurovascular circulation also can manifest lipotoxicity, which could have major effects on cognitive function. The penetration of integrative systems biology approaches is limited in this area of research, which reduces our capacity to gain an objective insight into the signal transduction and regulation dynamics at a systems level. To address this question, we treated human microvascular endothelial cells with triglyceride-rich lipoprotein (TGRL) lipolysis products and then we used genome-wide transcriptional profiling to obtain transcript abundances over four conditions. We then identified regulatory genes and their targets that have been differentially expressed through analysis of the datasets with various statistical methods. We created a functional gene network by exploiting co-expression observations through a guilt-by-association assumption. Concomitantly, we used various network inference algorithms to identify putative regulatory interactions and we integrated all predictions to construct a consensus gene regulatory network that is TGRL lipolysis product specific.ConclusionSystem biology analysis has led to the validation of putative lipid-related targets and the discovery of several genes that may be implicated in lipotoxic-related brain microvascular endothelial cell responses. Here, we report that activating transcription factors 3 (ATF3) is a principal regulator of TGRL lipolysis products-induced gene expression in human brain microvascular endothelial cell

    Development, Isolation and Characterisation of a New Non-Virulent Mimosine-Degrading \u3cem\u3eKlebsiella pneumoniae\u3c/em\u3e Strain from the Rumen Liquor of German Steers by Using IBT-Goettinger Bioreactor

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    The tropical legume Leucaena leucocephala (leucaena) has many uses, including: a potential source of firewood and timber; for soil erosion control (Dijkman 1950); to provide shade; to enhance soil fertility; and as a nutritious forage for animal feed (Ruskin 1977). It is widely used as forage for cattle in tropical agriculture (Shelton 1998). In Myanmar, leucaena is used as a protein source in urea-molasses multi-nutrient blocks for ruminants (Ni Ni Maw et al. 2004). However, the use of leucaena as ruminant feed is not without problems, because it contains mimosine, a toxic anti-nutritional factor limiting its use as animal feed. Jones (1981) reported the absence of toxicity when leucaena was fed to goats and cattle in Hawaii and Indonesia. According to the low dihydroxypyridine (DHP) in urine of those animals, it was assumed that they could degrade mimosine and DHP. Hawaiian goats, but not Australian goats, could degrade 3,4-DHP ruminally (Jones and Megarrity 1983). Inoculation of susceptible animals with rumen liquor containing mimosine-degrading bacteria protected against DHP toxicity in ruminants (Jones and Lowry 1984). For maintaining mimosine-degrading bacteria, the donor animals should be fed on leucaena continuously and it is expensive to maintain their veterinary care. Hence, we tried to develop mimosine-degrading ruminal bacteria using a fermenter, intending to produce a source of inoculum for the routine control of leucaena toxicosis in ruminants

    Parametric Study of Applied Stresses on Infiltration Modular Cells Installed under Roads

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    © 2016 The Authors. Published by Elsevier B.V. Modular geocellular units are applicable for the prevention and minimisation of stormwater runoff and flooding as a sustainable and cost-effective solution of road applications for drainage. The integrated units buried are exposed to the dead loads and live loads emerging from the surrounding soil pressure, pore water pressure and surcharge. Thus, a computer program using MATLAB is developed for the assessment of the total vertical and lateral earth pressure exerting on the modules complying with the Australian Standards AS 4678 (2002) and AS 5100.2(2004). Lateral earth pressure concept based on Rankine's theory is adopted in this model as the analytical approach. Closed-form solutions based on the fundamental soil mechanics are applied in the analytical calculation steps made. The model also considers different guidelines such as AASHTO LRFD Bridge Design Specifications (2010) for the stress distribution of vehicular loads according to the selected axle type. In consideration of the interaction of the moving vehicle and the bridge, the dynamic load allowance is also applied in terms of the static equivalent of the dynamic and vibratory effect as prescribed in AS 5100.2 (2004). Based on the results obtained, the numerical and theoretical results generated by the program provide considerable and influential factors in regarding to the parametric study and sensitivity analysis presented in this paper

    Review on Thermo-mechanical Approach in the Modelling of Geo-materials Incorporating Non-associated Flow Rules

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    © 2016 The Authors. Published by Elsevier B.V. Recently, there has been a burgeoning interest in developing constitutive soil models from the laws of thermodynamics, mainly due to the benefits that these models automatically obey them and the approach provides a well-established structure and reduces the need for 'ad hoc' postulates. A thermodynamic framework, also known as thermo-mechanical framework, has the capability to predict the behaviour of geotechnical materials, which requires the anticipated incorporation of non-associated flow rules. As it is very challenging to achieve acceptable accuracy in plasticity modelling of granular materials, this paper aims to review this framework not only to discuss the details of the major components but also to highlight the capability of generating non-associated flow rules in a natural way from thermo-mechanical principles. This approach introduces the use of internal variables to develop the two thermodynamic potentials (the free energy and the rate of dissipation functions), sufficient to derive the corresponding yield function, flow rule, isotropic and kinematic hardening rules as well as the basic elasticity law. It is shown that the non-associated flow rule can be derived naturally from the postulated stress-dependent dissipation increment function. Comparison has been made with stress-independent dissipation to demonstrate that the approach can also successfully explain the behaviour of standard materials with associated flow rules. The basic steps for the thermo-mechanical formulation for developing a constitutive model are also reviewed and summarised. Furthermore, the power of conventional mathematical technique, Legendre transformation, in the derivation of constitutive equations has been highlighted

    Genotypic and Chemical Influences on Fruit Growth of Tomato

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    A relationship between ovary size at anthesis and final fruit diameter of 12 tomato (Lycopersicon esculentum Mill.) cultivars with a range of fruit sizes, shapes, and maturation rates was determined. ‘Fireball’, ‘Michigan/Ohio Hybrid’, and ‘New Yorker’ produced nonfasciated, spherical fruits of intermediate maturation rate and showed a significantly higher correlation between ovary diameter at anthesis and final fruit diameter than ‘Small Fry’, ‘Roma VF’, ‘Early Cascade’, ‘Campbell 1327’, or ‘Ponderosa’. A linear regression of final fruit diameter at maturity on ovary diameter at anthesis of the cultivars was highly significant (r2 = 0.92**; ÿ = 22.5X - 0.3). Continuous root application of 0.01 µ�� BA to seedlings of ‘Fireball’ significantly delayed anthesis. A single foliar application of 0.37 mM NOA to ‘Fireball’ plants at the appearance of the first inflorescence significantly increased ovary diameter on the first inflorescence, but decreased ovary diameter on the second inflorescence. Treatment with NOA altered final fruit shape but not final fruit diameter. Single foliar applications of 0.1 mM GA stimulated stem and peduncle elongation but did not affect fruit size. Chemical names used: ß-naphthoxyacetic acid (NOA), N6-benzylaminopurine (BA), gibberellic acid, (GA)

    Water properties in the Suva Lagoon, Fiji

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    The salinity, temperature and turbidity in the lagoon are some important parameters for water quality which are continuously changing with the seasons and need to be studied because they are efficient indicators of variations in the lagoon and can transform the marine ecosystem. Results obtained showed that the salinity near the head of Laucala Bay during the wet-warm season was below 24.8 psu and was 33.7 psu during the drycool season. The temperature range for the Suva Lagoon during the wet-warm season was between 28.0–30.5 °C and between 24.5–25.5 °C during the dry-cool season. The turbidity in the lagoon was always above 3.0 FTU near the river mouths. The model salinity distribution compared well with the observed distribution from field data after the model was validated for salinity distribution
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