A Novel Sprague-Dawley Rat Model Presents Improved NASH/NAFLD Symptoms with PEG Coated Vitexin Liposomes

Chronic liver disease (CLD) is a global threat to the human population, with manifestations resulting from alcohol-related liver disease (ALD) and non-alcohol fatty liver disease (NAFLD). NAFLD, if not treated, may progress to non-alcoholic steatohepatitis (NASH). Furthermore, inflammation leads to liver fibrosis, cirrhosis, and hepatocellular carcinoma. Vitexin, a natural flavonoid, has been recently reported for inhibiting NAFLD. It is a lipogenesis inhibitor and activates lipolysis and fatty acid oxidation. In addition, owing to its antioxidant properties, it appeared as a hepatoprotective candidate. However, it exhibits low bioavailability and low efficacy due to its hydrophobic nature. A novel rat model for liver cirrhosis was developed by CCL4/Urethane co-administration. Vitexin encapsulated liposomes were synthesized by the ‘thin-film hydration’ method. Polyethylene glycol (PEG) was coated on liposomes to enhance stability and stealth effect. The diseased rats were then treated with vitexin and PEGylated vitexin liposomes, administered intravenously and orally. Results ascertained the liposomal encapsulation of vitexin and subsequent PEG coating to be a substantial strategy for treating liver cirrhosis through oral drug delivery.     

Microgravity Modifies the Phenotype of Fibroblast and Promotes Remodeling of the Fibroblast–Keratinocyte Interaction in a 3D Co-Culture Model

Microgravity impairs tissue organization and critical pathways involved in the cell–microenvironment interplay, where fibroblasts have a critical role. We exposed dermal fibroblasts to simulated microgravity by means of a Random Positioning Machine (RPM), a device that reproduces conditions of weightlessness. Molecular and structural changes were analyzed and compared to control samples growing in a normal gravity field. Simulated microgravity impairs fibroblast conversion into myofibroblast and inhibits their migratory properties. Consequently, the normal interplay between fibroblasts and keratinocytes were remarkably altered in 3D co-culture experiments, giving rise to several ultra-structural abnormalities. Such phenotypic changes are associated with down-regulation of α-SMA that translocate in the nucleoplasm, altogether with the concomitant modification of the actin-vinculin apparatus. Noticeably, the stress associated with weightlessness induced oxidative damage, which seemed to concur with such modifications. These findings disclose new opportunities to establish antioxidant strategies that counteract the microgravity-induced disruptive effects on fibroblasts and tissue organization.     

TLM modelling of diffusion,drift and recombination of charge carriers in semiconductors

The paper provides an extension to the one-dimensional TLM diffusion model. The extended diffusion node presented here models the exact transport equation with diffusion drift and recombination of charge carriers in semiconductors. A general algorithm for providing a numerical solution to the transport phenomena is also presented here. The analytical solution for infinitely long semiconductors is compared with the TLM numerical results.     

Removal of bisphenol A and 17α-ethinyl estradiol from landfill leachate using single-walled carbon nanotubes

In this study, the adsorption of bisphenol A (BPA) and 17α-ethinyl estradiol (EE2) from landfill leachate onto single-walled carbon nanotubes (SWCNTs) was investigated. Different leachate solutions were prepared by altering the pH, ionic strength, and dissolved organic carbon (DOC) in the solutions to mimic the varying water conditions that occur in leachate during the various stages of waste decomposition. The youngest and oldest leachate solutions contained varying DOC and background chemistry and were represented by leachate Type A (pH = 5.0; DOC = 2500 mg/L; conductivity = 12,500 μS/cm; [Ca²⁺] = 1200 mg/L; [Mg²⁺] = 470 mg/L) and Type E (pH = 7.5; DOC = 250 mg/L; conductivity = 3250 μS/cm; [Ca²⁺] = 60 mg/L; [Mg²⁺] = 180 mg/L). These solutions were subsequently combined in different ratios to produce intermediate solutions, labeled B-D, to replicate time-dependent changes in leachate composition. Overall, a larger fraction of EE2 was removed as compared to BPA, consistent with its higher log K_OW value. The total removal of BPA and EE2 decreased in older leachate solutions, with the adsorptive capacity of SWCNTs decreasing in the order of leachate Type A > Type B > Type C > Type D > Type E. An increase in the pH from 3.5 to 11 decreased the adsorption of BPA by 22% in young leachate and by 10% in old leachate. The changes in pH did not affect the adsorption of EE2 in the young leachate, but did reduce adsorption by 32% in the old leachate. Adjusting the ionic strength using Na⁺ did not significantly impact adsorption, while increasing the concentration of Ca²⁺ resulted in a 12% increase in the adsorption of BPA and a 19% increase in the adsorption of EE2. DOC was revealed to be the most influential parameter in this study. In the presence of hydrophilic DOC, represented by glucose in this study, adsorption of the endocrine disrupting compounds (EDCs) onto the SWCNTs was not affected. In the absence of SWCNTs, hydrophobic DOC (i.e., humic acid) adsorbed 15-20% of BPA and EE2. However, when the humic acid and SWCNTs were both present, the overall adsorptive capacity of the SWCNTs was reduced. Hydrophobic (π-π electron donor-acceptor) interactions between the EDCs and the constituents in the leachate, as well as interactions between the SWCNTs and the EDCs, are proposed as potential adsorption mechanisms for BPA and EE2 onto SWCNTs.     

Studies on mechanical and biodegradability properties of PVA/lignin blend films

The mechanical and biodegradation properties of polyvinyl alcohol/lignin blended films have been studied. The biodegradable composite films were developed by mechanical mixing followed by film casting method using poly (vinyl alcohol) (PVA), with lignin in different compositions. The progress of biodegradation was evidenced by means of the soil burial test. There was also an evaluation of the weight loss of the samples at the end of the biodegradation process. Blending the PVA with lignin improves tensile strength and the modulus of elasticity and causes a slight decrease in the elongation at break. The best tensile mechanical properties of a PVA/lignin blend were at ratio 2:30 where the tensile strength was 38 MPa, elastic modulus 83.22 MPa and elongation at break 213.9%. Blends of various PVA/lignin ratios have shown transparency, flexibility and good mechanical properties. Film composites also showed good biodegradability. The addition of lignin to the PVA matrix increases the degradation rate of the blends. The weight loss is affected by the composition of the blend, and by the nature of the microorganisms in the soil. PVA/lignin film may be potentially suitable as eco-friendly packaging materials.     

Graft polymerization of methyl methacrylate onto wool initiated by a hydrogen peroxide-sodium thiosulphate redox system. Part II kinetics and mechanism of the grafting reaction

Methyl methacrylate was grafted onto wool in the presence of an aqueous dioxane solution with a hydrogen peroxide-sodium thiosulphate initiator system, using the optimum conditions found in our previous paper¹⁹. It was stated that up to 90% conversion for the rate of reaction the following equation holds: \documentclass{article}\pagestyle{empty}\begin{document}${\rm R}_{\rm p} = - \frac{{{\rm d}\left[ {\rm M} \right]}} {{{\rm dt}}} = {\rm K} \cdot \left[ {\rm M} \right]^{1.5}$\end{document} where R_p is the overall rate of the graft polymerization, and [M] is the monomer concentration at the time t. The degree of polymerization of the isolated poly(methyl methacrylate) was found to be linearly proportional with the monomer concentration [M]. Investigations of the effect of the ratio of solvent to monomer concentration [S]/[M] on the reciprocal of the degree of polymerization showed that there was no chain transfer caused by the solvent dioxane. The number average molecular weight M?_n of the polymer separated from the grafted wool was found to be within the range of 3–15.9 × 10⁶ as determined by viscosimetry. The molecular weight distribution of the isolated poly(methyl methacrylate) samples was determined by turbidimetric titration. The following relationship was established between the volume fraction of the non-solvent, γ and the number average molecular weight M?ⁿ. of poly(methyl methacrylate): \documentclass{article}\pagestyle{empty}\begin{document}$\gamma = - 0.0285 + \frac{{50.54}}{{\sqrt[3]{{\overline M _n }}}}. $\end{document} The molecular weight distribution curves were found to be rather homogeneous indicating approximately the same chain length of the grafted poly(methy1 methacrylate) on the wool backbone. It was stated before³³ that the number average molecular weight could be determined from the inflection point of the turbidimetric curves. This method can be used for determining the molecular weight of all kinds of poly(methy1 methacrylate) occurring in practice.     

Synthesis of trideuteratedO-alkyl platelet activating factor and lyso derivatives

Racemic heavy isotope analogs of 1-O-alkyl-sn-glycero-3-phosphocholine (lysoPAF) and 1-O-alkyl-2-O-acetyl-sn-glycero-3-phosphocholine (PAF) were prepared for use as internal standards to facilitate quantitative studies based on mass spectrometry. Starting from pentadencane-1,15-diol andrac-glycerol-1,2-acetonide, a convergent synthesis of 1-O-[16′-²H₃]hexadecyl and 1-O-[18′-²H₃]octadecylrac-glycero-3-phosphocholine and their acetyl derivatives is described. Three deuterium atoms were introduced at the terminal position of the 1-O-alkyl group by displacement of thep-toluensulfonyl group from 1-O-alkyl-15′-p-toluensulfonate and 1-O-alkyl-17′-p-toluensulfonate with [²H₃]-methylmagnesium iodide. The 1-O-alkyl-17′-p-toluensulfonate was obtained by reaction of the 1-O-alkyl-15′-p-toluensulfonate with allylmagnesium bromide, followed by reductive ozonolysis and treatment withp-toluenesulfonyl chloride. The hydroxyl group at C-2 was protected by a benzyl group and removed at a late stage in the synthesis. This provided the corresponding lysoderivatives or allowed preparation of racemic PAF by subsequent acetylation of the free hydroxy group. The phosphocholine moiety was introduced at glycerol C-3 by reaction with bromoethyldichlorophosphate and trimethylamine. The synthetic compounds were analyzed by FAB/MS and GC/NICIMS. They were shown to contain less than 0.6% protium impurity.     

A comparison of Zayandehrood River water values for agriculture and the environment

River water management is challenging not only since they are open systems with changing physical structures, but also because the water values are mostly unknown over varied sectors. If policymakers grasp water values, water management will be more efficient. This research intends to examine the values of water in agriculture, which receives the most substantial portion of water resources, with the values of water in the environment in Isfahan located in the Zayandehrood River basin of Iran. The consequences of contingent valuation and production function methods revealed that per cubic metre value of water is 13 times higher in the environment than agriculture. The government should reconsider the higher value of the environment despite it is a non‐market value. The contingent valuation model additionally proved that women exhibited 21% more willingness to pay than men in order to protect the environment; however, they are paid less by 36%.     

Void Nucleation and Growth in Dual-Phase Steel 600 during Uniaxial Tensile Testing

Commercial dual-phase (DP) steel in sheet form and comprised of ferrite, martensite, and bainite was subjected to uniaxial tension up to fracture. The damage characteristics were studied through extensive quantitative metallography and scanning electron microscope (SEM) observations of polished sections and fracture surfaces of failed specimens. The observed void nucleation mechanisms include nucleation at the martensite/ferrite interface or triple junction (most predominant), nucleation due to the cracking of martensite particles, and nucleation at the inclusions. The void characteristics in terms of area fraction, void density, void size ranges, and void orientations were analyzed as a function of thickness strain from various regions of the different uniaxial tensile test specimens taken to fracture. The damage analysis suggests that the void nucleation occurs during the entire deformation process with an almost constant rate and this rate reduces before fracture. A nucleation strain of 0.15 has been estimated for this material.