Analyzing A-series gangliosides in neurons following exposure to glutamate

Neurons within different brain regions have varying levels of vulnerability to external stress and therefore respond differently to injury. A potential reason to explain this may lie within a key lipid class of the cell’s plasma membrane called gangliosides. These glycosphingolipid species have been shown to play various roles in the maintenance of neuronal viability. The purpose of this study is to use electrospray ionization mass spectrometry (ESI-MS) technique and immunohistochemistry to evaluate the temporal changes in the expression profiles of various ganglioside species during the course of neurodegeneration in rat primary cortical neurons exposed to glutamate toxicity. Primary embryonic (E18) rat cortical neurons were cultured to DIV14. Glutamate toxicity was induced for 1, 3, 6 and 24 h. Immunofluorescence was used to stain for GM1 and GM3 species and ESI-MS was used to quantify the ganglioside species expressed within these injured neurons, which were compared to expression profiles of healthy neurons. Neurons were also pretreated with GM1 24 h before glutamate exposure to assess the level of neuroprotection conferred by GM1. Microglia were also activated using amyloid-beta oligomer and stained for GM1 and GM3 expression. ESI-MS data revealed that d16:1 and d18:1 GM1 species were upregulated in neurons exposed to glutamate while no significant changes were observed for GM2 and GM3 expression. Furthermore, neurons that were pretreated with GM1 showed increased viability compared to untreated neurons when exposed to glutamate. Immunofluorescence revealed an elevated expression of GM3 in activated microglia compared to controls. These data suggests that different gangliosides and cells within the CNS play diverse roles in the process of neurodegeneration

Analytical Modeling of Rheological Postbuckling Behavior of Wood-Based Composite Panels Under Cyclic Hygro-Loading

This study was conducted to develop analytical models to predict postbuckling behavior of woodbased composite panels under cyclic humidity conditions. Both the Rayleigh method and von Karman theory of nonlinear plate with imperfection were used to obtain a closed form solution to the hygrobuckling and postbuckling. In addition, mechano-sorptive creep effects were also taken into account for the derivation of analytical models. The closed-form solutions derived for both isotropic and orthotropic materials showed a good agreement with the experimental results in terms of the center deformation of hardboard, especially in the case of the edge movements. The unrecovery deformation was much greater at the first cycle and then decreased as the number of cyclic hygro-loading increased

One-pot Enzymatic Synthesis of Deoxy-thymidine-diphosphate (TDP)-2-deoxy-∝-d-glucose Using Phosphomannomutase

Production of deoxy-thymidine-diphosphate (TDP)-sugars as substrates of glycosyltransferases, has been one of main hurdles for combinatorial antibiotic biosynthesis, which combines sugar moiety with aglycon of various antibiotics. Here, we report the one-pot enzymatic synthesis of TDP-2-deoxy-glucose employing high efficient TMP kinase (TMK; E.C. 2.7.2.12), acetate kinase (ACK; E.C. 2.7.1.21), and TDP-glucose synthase (TGS; E.C. 2.7.7.24) with phosphomannomutase (PMM; E.C. 5.4.2.8). In this study, replacing phosphoglucomutase (PGM; E.C. 5.4.2) by PMM from Escherichia coli gave four times higher specific activity on 2-deoxy-6-phosphate glucose, suggesting that the activity on 2-deoxy-glucose-6-phosphate was mainly affected by PMM activity, not PGM activity. Using an in vitro system starting from TMP and 2-deoxy-glucose-6-phosphate glucose, TDP-2-deoxy-glucose (63% yield) was successfully synthesized. Considering low productivity of NDP-sugars from cheap starting materials, this paper showed how production of NDP-sugars could be enhanced by controlling mutase activity

Friction Tubes to Generate Nanobubble Ozone Water with an Increased Half-Life for Virucidal Activity

Nanobubbles and related technologies are expected to be highly utilized in water resource-based industries such as water purification, crops, horticulture, medicine, bio, and sterilization. Ozone, a chemical with high sterilizing power, is known as a natural substance that is reduced to oxygen and water after reacting with pollutants. Ozone water, which is generated by dissolving ozone in water, has been used in various industrial sectors such as medical care, food, and environment. Due to the unstable molecular state of ozone, however, it is difficult to produce, use, and supply ozone at industrial sites in a stable manner. This study proposed a method for constructing a system that can generate high-concentration ozone water in large quantities using low power in real time and maintaining the concentration of the generated ozone water over the long term. Friction tubes (called 'nanotube') played a key role to generate nanobubble ozone water with an increased half-life for virus killing activity. In addition, the safety of ozone water during its spray into the air was explained, and virucidal activity test cases for the influenza A (H1N1/A/PR8) and COVID-19 (SARS-CoV-2) virus using high-concentration ozone water as well as its technical efficacy were described

Generation of high concentration nanobubbles based on friction tubes

Nanobubble-related technologies have been confirmed to be useful in various fields such as climate change and the environment as well as water-based industries such as water purification, crops, horticulture, medical care, bio, and sterilization. However, a method of mass production in real time enough to apply nano-bubbles to the industry has not yet been developed. We explored the mechanism of nano-bubble water generation by friction between water and walls and developed a tube device applying the shape of the flow path to maximize the friction in the fluid passing through the flow path. It also describes the case of real-time and low-power mass production of nanobubbles and its technical utility. We found that the friction of nanotubes alone can easily and quickly improve the production of nanobubbles with small particle size in real time; by increasing the shearing pressure while increasing the effective friction constant value, the particle size of nanobubbles can be smaller while increasing the particle concentration.Comment: 24 pages, 24 figures, 6 table