Characterization of the recruitment of intimal smooth muscle cells in vascular disease

Intimal hyperplasia occurs as a response to a variety of vascular insults and results in vascular stenosis, and organ ischemia. This process represents a fundamental component of atherosclerosis, venous graft stenonsis, and allograft arteriopathy in solid organ transplants. Smooth muscle cells (SMCs), and their associated extracellular matrix (ECM) form major components of intimal hyperplasia. We hypothesize that chemokines play a critical role in SMC migration into such intimal lesions. A number of chemokine-chemokine receptor interactions that mediate inflammatory cell recruitment have been characterized. However, the specific chemokine- chemokine receptor pathways that contribute to SMC recruitment are not known. The aims of this study are to examine the expression of C-C chemokine receptor 1 (CCR1) on medial SMCs (MSMCs), and to test its functionality in SMC recruitment. SMCs were derived from murine aortas; cultures were >95% SMC as demonstrated by the expression of smooth muscle α-actin (SMA), calponin, smooth muscle myosin heavy chain (SM-MHC). Interferon-gamma (IFN-γ) and Tumor necrosis factor- alpha (TNF-α) - stimulated MSMCs express CCR1 with a peak expression between 30 h and 48 h after cytokine stimulation. The functionality of receptors was initially demonstrated by agonist-induced calcium mobilization: the addition of CCR1 ligands, Regulated on activation, Normal T cell expressed and secreted (RANTES) and Macrophage inflammatory protein -1α (MIP-1α) to MSMCs caused an increase in intracellular Ca2+ concentration. Blockade of CCR1 by BX471, a CCR1 antagonist, inhibited the Ca2+ mobilization induced by RANTES and MIP-1α. The results suggest that up-regulation of CCR1 expression on cytokine-stimulated SMCs may facilitate recruitment into intimal lesions through endothelial-derived chemokine expression

Numerical Study of the Features of Ti-Nb Alloy Crystallization during Selective Laser Sintering

The demand for implants with individual shape requires the development of new methods and approaches to their production. The obvious advantages of additive technologies and selective laser sintering are the capabilities to form both the external shape of the product and its internal structure. Recently appeared and attractive from the perspective of biomechanical compatibility are beta alloys of titanium-niobium that have similar mechanical properties to those of cortical bone. This paper studies the processes occurring at different stages of laser sintering using computer simulation on atomic scale. The effect of cooling rate on the resulting crystal structure of Ti-Nb alloy was analysed. Also, the dependence of tensile strength of sintered particles on heating time and cooling rate was studied. It was shown that the main parameter, which determines the adhesive properties of sintered particles, is the contact area obtained during sintering process. The simulation results can both help defining the technological parameters of the process to provide the desired mechanical properties of the resulting products and serve as a necessary basis for calculations on large scale levels in order to study the behaviour of actually used implants

Mesoporous Three-Dimensional Graphene Networks for Highly Efficient Solar Desalination under 1 Sun Illumination

Solar desalination via thermal evaporation of abundant seawater is one of the most promising technologies to address the serious global water scarcity problem since it does not require additional supporting energy other than infinite solar energy for generating clean water. However, low efficiency and a large amount of heat loss are considered critical limitations of solar desalination technology. The combination of mesoporous three-dimensional graphene networks (3DGNs) with a high solar absorption property and water transporting wood pieces with a thermal insulation property has shown greatly enhanced solar to vapor conversion efficiency. 3DGN deposited on a wood piece provides a world record value of solar to vapor conversion efficiency, about 91.8%, under one sun illumination and excellent desalination efficiency of five orders salinity decrement. The mass-producible 3DGN enriched with many mesopores efficiently releases the vapors from the enormous area of the surface by heat localization on the top surface of the wood piece. Because the efficient solar desalination device made by 3DGN on the wood piece is highly scalable and inexpensive, it could serve as one of the main sources for the worldwide supply of purified water achieved via earth-abundant materials without an extra supporting energy source

Three-dimensional solar steam generation device with additional non-photothermal evaporation

The evaporation sites of a solar desalination device were expanded from conventional 2D to a new type of 3D by leaving the side area of the porous water transporter exposed to the air. The 3D solar desalination device permits not only photothermal distillation by the photoabsorbers at the top under sunlight illumination, but also additional non-photothermal evaporation on the side of the water transporter that works even at night by exploiting environmental heat. For the first time, we developed a unique configuration of water transport exposed to the environment with a great contribution to an active site increase and confirmed the significant impact of the active site increase on the solar desalination performance by systematic and strong pieces of evidence. Due to the effective utilization of enormous evaporation sites on the top and side surfaces in the 3D configuration, the device exhibited a significant steam generation rate of similar to 0.74 g/h under 1 sun illumination, which is similar to 1.5 times higher than the maximum value achieved with photothermal evaporation only. Our study suggests an innovative change which incorporates additional non-photothermal evaporation in the solar desalination device can be a straightforward and efficient way to address clean water deficiencies worldwide in the future

Simultaneous determination of 31 Sulfonamide residues in various livestock matrices using liquid chromatography-tandem mass spectrometry

Abstract The widespread use of sulfonamides can result in the residue of sulfonamides in the foods of animal origin that are the major concerns of consumers and regulatory bodies due to their adverse reaction such as the development of antibiotic resistance. A rapid and efficient multi-residue analytical method was developed to screen and confirm 31 sulfonamides in livestock samples in a single run, using ultra-high-performance liquid chromatography combined with comprehensive mass spectrometric approaches. In this study, a novel sample preparation procedure was used, based on a modified QuEChERS method (Quick, Easy, Cheap, Effective, Rugged, and Safe). The linearity, sensitivity, accuracy, and precision of the method were validated according to the Codex guidelines. The response of the detector was linear for each target compound over a wide concentration range, with a correlation coefficient (r2) greater than 0.98. The limit of detection (LOD) and limit of quantification (LOQ) ranged from 0.3 to 5 ng g −1 and from 1 to 19 ng g −1 and the average recoveries (%) for three laboratories ranged from 85 to 109% with a CV (n = 5) below 22%. The applicability of this screening method was verified using real livestock samples. The proposed analytical method achieves identification and quantification of target sulfonamides at trace levels in a short analysis time. None of the samples contained residues that exceeded the maximum residue limit (MRL)