18 research outputs found
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Probiotic Yeast Inhibits VEGFR Signaling and Angiogenesis in Intestinal Inflammation
Background and Aims Saccharomyces boulardii (Sb) can protect against intestinal injury and tumor formation, but how this probiotic yeast controls protective mucosal host responses is unclear. Angiogenesis is an integral process of inflammatory responses in inflammatory bowel diseases (IBD) and required for mucosal remodeling during restitution. The aim of this study was to determine whether Sb alters VEGFR (vascular endothelial growth factor receptor) signaling, a central regulator of angiogenesis. Methods: HUVEC were used to examine the effects of Sb on signaling and on capillary tube formation (using the ECMatrix™ system). The effects of Sb on VEGF-mediated angiogenesis were examined in vivo using an adenovirus expressing VEGF-A(164) in the ears of adult nude mice (NuNu). The effects of Sb on blood vessel volume branching and density in DSS-induced colitis was quantified using VESsel GENeration (VESGEN) software. Results: 1) Sb treatment attenuated weight-loss (p<0.01) and histological damage (p<0.01) in DSS colitis. VESGEN analysis of angiogenesis showed significantly increased blood vessel density and volume in DSS-treated mice compared to control. Sb treatment significantly reduced the neo-vascularization associated with acute DSS colitis and accelerated mucosal recovery restoration of the lamina propria capillary network to a normal morphology. 2) Sb inhibited VEGF-induced angiogenesis in vivo in the mouse ear model. 3) Sb also significantly inhibited angiogenesis in vitro in the capillary tube assay in a dose-dependent manner (p<0.01). 4) In HUVEC, Sb reduced basal VEGFR-2 phosphorylation, VEGFR-2 phosphorylation in response to VEGF as well as activation of the downstream kinases PLCγ and Erk1/2. Conclusions: Our findings indicate that the probiotic yeast S boulardii can modulate angiogenesis to limit intestinal inflammation and promote mucosal tissue repair by regulating VEGFR signaling
Sustainable and renewable energy from biomass wastes in palm oil industry: A case study in Malaysia
Palm oil is one of the most important oils in the world and huge amounts of palm biomass wastes are generated through palm oil extracting process which could endanger the environment. Meanwhile, electricity shortage is getting worse due to lack of fossil fuel. To convert biomasses from palm oil industry for power generation is a beneficial approach for both power shortage and environmental degradation. In order to investigate and optimize the generation process of power and heat from the waste biomass in palm oil industry, an analytic study of a combined heat and power plant in a palm oil mill fuelled with sustainable and renewable biomass wastes was conducted using ECLIPSE software through a case study in Malaysia. The resources of the biomass wastes in the mill were identified and the samples were collected on site. The waste samples were analysed in laboratory and their calorific value, chemical composition and biomethane potential were found. A simulation model was then set up using ECLIPSE software and the model was validated using the practical data of the CHP plant. Three different combinations of the biomass wastes, including EFB and Shell as fuel for power generation, MF co-firing with Biogas, and power generation using KS, EFB and Biogas with preheaters, were used in the simulation. It was found that all of the three combinations were able to produce enough electrical power and heat (steam) to meet the power and heat demand for the production process. The simulation results indicated that the palm solid biomass wastes and the biogas produced by mill effluent were able to provide enough sustainable and renewable fuel for the palm oil production process; and it is possible to provide extra electricity for the nearby area, which is one of the best option for utilization of palm oil biomass wastes.Highlights> A feasibility study of a palm oil biomass CHP plant was conducted using ECLIPSE.> Three different combinations of biomass wastes were optimized through simulation.> It can produce enough electricity and heat (steam) for palm oil production demand.> It has great potential to provide electricity to the grid as well
Investigation on Synthesis, Stability, and Thermal Conductivity Properties of Water-Based SnO2/Reduced Graphene Oxide Nanofluids
With the rapid development of industry, heat removal and management is a major concern for any technology. Heat transfer plays a critically important role in many sectors of engineering; nowadays utilizing nanofluids is one of the relatively optimized techniques to enhance heat transfer. In the present work, a facile low-temperature solvothermal method was employed to fabricate the SnO2/reduced graphene oxide (rGO) nanocomposite. X-ray diffraction (XRD), thermogravimetric analysis (TGA), X-ray photoelectron spectroscope (XPS), Raman spectroscopy, and transmission electron microscopy (TEM) have been performed to characterize the SnO2/rGO nanocomposite. Numerous ultrasmall SnO2 nanoparticles with average diameters of 3–5 nm were anchored on the surface of rGO, which contain partial hydrophilic functional groups. Water-based SnO2/rGO nanofluids were prepared with various weight concentrations by using an ultrasonic probe without adding any surfactants. The zeta potential was measured to investigate the stability of the as-prepared nanofluid which exhibited great dispersion stability after quiescence for 60 days. A thermal properties analyzer was employed to measure thermal conductivity of water-based SnO2/rGO nanofluids, and the results showed that the enhancement of thermal conductivity could reach up to 31% at 60 °C under the mass fraction of 0.1 wt %, compared to deionized water
Nanocomposites LiMnxFe1-xPO4/C synthesized via freeze drying assisted sol-gel routine and their magnetic and electrochemical properties
Nanocomposites LiMnxFe1-xPO4/C (x = 1, 5/6, 2/3, 1/2) are synthesized by a sol-gel route combined with freeze drying. Fe2+ substituted samples coated by high-ordered carbon have the same olivine structure of LiMnPO4/C but reduced cell volumes. Fe2+ substituting greatly influences magnetic characteristics of LiMnPO4/C and slight amounts of Fe2P impurity in Fe2+ doped samples are verified by magnetic tests. Fe2+ substituted samples exhibit much better electrochemical properties. Among them, LiMn1/2Fe1/2PO4/C displays the best rate capacity and cyclic stability. Its initial discharge capacity reaches 140.1 mAh g−1 and remains at 132.5 mAh g−1 after 100 cycles at 2C, remarkably higher than those of LiMnPO4/C. The superior electrochemical performances are mainly attributed to small charge-transfer impedance, fast Li+ diffusion, residual carbon and existence of Fe2P with excellent electronic conductivity
Improved rate and cycle performance of nano-sized 5LiFePO4$Li3V2(PO4)3/C via high-energy ball milling assisted carbothermal reduction
Nano-sized 5LiFePO4·Li3V2(PO4)3/C composite was synthesized via improved carbothermal reduction combined high-energy ball milling. XRD results reveal that the composite is composed of olivine LiFePO4 and monoclinic Li3V2(PO4)3 phases. Meanwhile small amounts of V3+ and Fe2+ as dopants entered into the lattices of LiFePO4 and Li3V2(PO4)3, respectively. Trace amounts of Fe2O3 in LiFePO4/C and Fe2P in 5LiFePO4·Li3V2(PO4)3/C were identified and quantified by magnetic tests. And magnetic parameters of 5LiFePO4·Li3V2(PO4)3/C are significantly different from LiFePO4/C. The 5LiFePO4·Li3V2(PO4)3/C presents initial discharge specific capacities of 145.2 mAh g¿1 and 133.9 mAh g¿1 and no capacity attenuations after 50 cycles can be observed at 2C and 5C respectively. Compared with LiFePO4/C, its rate capability and cyclic stability are both enhanced greatly. The mutual doping, synergistical effect of LiFePO4 and Li3V2(PO4)3 and contribution of Fe2P are mainly responsible for the excellent electrochemical performances
Vascular network results (mean ± std dev).
<p>Vascular network results (mean ± std dev).</p
Avascular spaces (AVS) results (mean ± std dev).
<p>Avascular spaces (AVS) results (mean ± std dev).</p
Oral administration of Sb reduced DSS-colitis induced weight loss, histological damage and neo-vascularization in mouse colon.
<p>We used the murine DSS-colitis model to assess the effect of Sb on neo-vascularization in acute colitis. We administered DSS (4% for 5 days) to mice to induce colitis. <b>1A)</b> Daily administration of Sb by gavage significantly attenuated weight-loss (N = 5, *p<0.05, **p<0.01). Data points represent mean relative weight ± standard error. <b>1B)</b> Histological scores for several parameters of colonic inflammation on Day 5 were evaluated [control (N = 5), DSS alone (N = 5), DSS plus Sb (N = 5)]. Data points represent mean score ± standard error, <sup>**</sup>, p<0.01. Representative H/E stained colonic images are listed. <b>1C)</b> Confocal fluorescence images of the colonic microvasculature were taken 10 minutes after i.v injection of Alexa 647 WGA. Three dimensional image reconstructions were translated into two dimensional grayscale images and binarized to black-and-white vascular patterns for analysis using VESGEN software. Representative images are shown. <b>1D)</b> Quantitative data are presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0064227#pone-0064227-t001" target="_blank">Tables 1</a> and <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0064227#pone-0064227-t002" target="_blank">2</a>. Comparisons of vascular network and avascular space indices among control, DSS and DSS+ Sb groups. Compared to control mice, the DSS group had significantly increased numbers of branch points and density of vessel endpoints (p = 0.004, p = 0.02 respectively). Sb treatment significantly reduced these DSS effects (p = 0.045, p = 0.02 respectively). The mean area per AVS (µm<sup>2</sup>) in the lamina propria was reduced in the DSS group compared to the control group (p = 0.01). Sb treatment normalized this effect (p = 0.02).</p