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Epoxy acrylate is produced by esterifying epoxy resin and acrylic acid through a ring-opening reaction. This process is highly exothermic and can be challenging to control gel formation. The thermal hazards of epoxy acrylate preparation were evaluated in this study by investigating the ring-opening esterification reaction between acrylic acid (AA) and bisphenol A epoxy resin (E-51) catalyzed by triethylamine (TEA). The heat release during the reaction process was analyzed using a reaction calorimeter (RC1mx) to simulate industrial conditions. Increasing the TEA catalyst content from 0.3 to 1.0 mass% resulted in a significant rise in reaction conversion from 75.35 ± 0.10% to 98.44 ± 0.10%. Differential scanning calorimetry (DSC) and accelerating rate calorimeter (ARC) were used to examine the thermal runaway process during epoxy acrylate synthesis. Increasing the TEA content from 0.3 to 1.0 mass% decreased the initial reaction temperature from 60.16 ± 0.62 to 45.33 ± 0.40 °C and the critical temperature of side reactions from 153.71 ± 1.51 to 117.85 ± 1.19 °C. The severity of the runaway was classified as medium at process temperatures of 80–110 °C. This study highlights the importance of considering reaction conditions to prevent uncontrolled reactions during epoxy acrylate synthesis, providing valuable insights for industrial epoxy acrylate preparation. [ABSTRACT FROM AUTHOR]

Epoxidized soybean oil (ESO) is a sustainable alternative that reduces emissions of volatile organic compounds, enhances coating and adhesion properties, and has a wide range of applications in bio-based composites. However, the industrial-scale production of ESO through the Prilezhaev reaction presents challenges in terms of temperature regulation and the potential for uncontrolled thermal reactions. This study aimed to investigate the thermal hazards associated with ESO production using hydrogen peroxide. We analyzed the reaction mechanism and exothermic behavior using dynamic differential scanning calorimetry (DSC), accelerated calorimetry (ARC), reaction calorimetry (RClmx), and in situ Fourier transform infrared spectroscopy (FTIR). Our findings demonstrated that the addition of sulfuric acid and formic acid raised the onset decomposition temperature of hydrogen peroxide. We also identified two exothermic phases (epoxidation of the double bond and degradation of the organic matter) and observed a rapid increase in temperature and pressure, posing a safety risk. Formic acid formation and epoxidation of the double bond were the main steps of the reaction mechanism, and the exothermic behavior stems mainly from the latter. We assessed the thermal hazard level using a risk matrix and the Stoessel criterion, which highlighted the high risk of thermal runaway without proper cooling and temperature control. This paper offers practical guidance for mitigating these risks in the industry. [ABSTRACT FROM AUTHOR]

Based on the Prileschajet reaction, formic acid (FA), hydrogen peroxide (H2O2) were selected as the oxidants and sulfuric acid (H2SO4) as the catalyst to establish the reaction model. Initially, the reaction mechanism of the system was explained by investigating the process conditions of soybean oil (SBO), and the results showed that the two-phase (oil–water) reaction system was similar to the quasi-homogeneous system. Consequently, a mathematical model of quasi-homogeneous system was established to describe the epoxidation process of SBO. Although the rate constants indicated that the formation of PFA was a decisive step of the whole system, PFA still exists as an intermediate in the system. Furthermore, the activation energy of PFA decomposition indicated the temperature sensitivity of PFA, making it prone to easy decomposition. This strongly suggests that the decomposition of PFA and its subsequent consequences are not to be treated as negligible phenomena. [ABSTRACT FROM AUTHOR]

SARS-Cov-2 infection, which has caused the COVID-19 global pandemic, triggers cellular senescence. In this study, we investigate the role of the SARS-COV-2 spike protein (S-protein) in regulating the senescence of RPE cells. The results showed that administration or overexpression of S-protein in ARPE-19 decreased cell proliferation with cell cycle arrest at the G1 phase. S-protein increased SA-β-Gal positive ARPE-19 cells with high expression of P53 and P21, senescence-associated inflammatory factors (e.g., IL-1β, IL-6, IL-8, ICAM, and VEGF), and ROS. Elimination of ROS by N-acetyl cysteine (NAC) or knocking down p21 by siRNA diminished S-protein-induced ARPE cell senescence. Both administrated and overexpressed S-protein colocalize with the ER and upregulate ER-stress-associated BIP, CHOP, ATF3, and ATF6 expression. S-protein induced P65 protein nuclear translocation. Inhibition of NF-κB by bay-11-7082 reduced S-protein-mediated expression of senescence-associated factors. Moreover, the intravitreal injection of S-protein upregulates senescence-associated inflammatory factors in the zebrafish retina. In conclusions, the S-protein of SARS-Cov-2 induces cellular senescence of ARPE-19 cells in vitro and the expression of senescence-associated cytokines in zebrafish retina in vivo likely by activating ER stress, ROS, and NF-κb. These results may uncover a potential association between SARS-cov-2 infection and development of AMD. [ABSTRACT FROM AUTHOR]

This study aims to evaluate the efficacy of 0.01% atropine eye drops in preventing myopia shift and myopia onset in premyopic children. A prospective, randomized, double-masked, placebo-controlled, and crossover trial was conducted over 13 months. Sixty premyopic children aged 6–12 years with cycloplegic spherical equivalent refraction (SER) > − 0.75 D and ≤ + 0.50 D in both eyes were assigned in a 1:1 ratio to receive one drop of 0.01% atropine or placebo once nightly for 6 months (period 1), followed by a 1-month recovery period. Then, the 0.01% atropine group was crossed over to the placebo group, and the latter was crossed over to the 0.01% atropine group for another 6 months (period 2). The primary outcomes were changes in SER and axial length (AL), and the secondary outcomes were the proportion of myopia onset (SER ≤ − 0.75D) and fast myopic shift (change in SER ≤ − 0.25D) in the two periods. Generalized estimating equation (GEE) model performed a statistically significant treatment effect of 0.01% atropine compared with placebo (pSER = 0.02, pAL < 0.001), with a mean SER and AL difference of 0.20D (− 0.15 ± 0.26D vs. − 0.34 ± 0.34D) and 0.11 mm (0.17 ± 0.11 mm vs. 0.28 ± 0.14 mm) in period 1, and 0.17D (− 0.18 ± 0.24D vs. − 0.34 ± 0.31D) and 0.10 mm (0.15 ± 0.15 mm vs. 0.24 ± 0.11 mm) in period 2. The GEE model showed that the proportion of myopia onset (p = 0.004) and fast myopic shift (p = 0.009) was significantly lower in the 0.01% atropine group than that in the placebo group. The period effect was not statistically significant (all p > 0.05). A total of 0.01% atropine significantly prevented myopic shift, axial elongation, and myopia onset in premyopic schoolchildren in central Mainland China. Conclusion: Within the limits of only two consecutive 6-month observation period, 0.01% atropine eye drops effectively prevented myopic shift, axial elongation, and myopia onset in premyopic children. Trial registration: This trial was registered in the Chinese Clinical Trial Registry (Registration number: ChiCTR2000034760). Registered 18 July 2020. What is Known: • Minimal studies on interventions for pre-myopia, despite the International Myopia Institute stating that preventing myopia is an "even more valuable target" for science and practice than reducing progression after onset. What is New: • A total of 0.01% atropine eye drops may safely and effectively reduce the proportion of myopia onset and fast myopic shift in premyopic schoolchildren. [ABSTRACT FROM AUTHOR]

Inflammatory demyelination and axonal injury of the optic nerve are hallmarks of optic neuritis (ON), which often occurs in multiple sclerosis and is a major cause of visual disturbance in young adults. Although a high dose of corticosteroids can promote visual recovery, it cannot prevent permanent neuronal damage. Novel and effective therapies are thus required. Given the recently defined capacity of matrine (MAT), a quinolizidine alkaloid derived from the herb Radix Sophorae flavescens, in immunomodulation and neuroprotection, we tested in this study the effect of matrine on rats with experimental autoimmune encephalomyelitis, an animal model of multiple sclerosis. MAT administration, started at disease onset, significantly suppressed optic nerve infiltration and demyelination, with reduced numbers of Iba1+ macrophages/microglia and CD4+ T cells, compared to those from vehicle-treated rats. Increased expression of neurofilaments, an axon marker, reduced numbers of apoptosis in retinal ganglion cells (RGCs). Moreover, MAT treatment promoted Akt phosphorylation and shifted the Bcl-2/Bax ratio back towards an antiapoptotic one, which could be a mechanism for its therapeutic effect in the ON model. Taken as a whole, our results demonstrate that MAT attenuated inflammation, demyelination and axonal loss in the optic nerve, and protected RGCs from inflammation-induced cell death. MAT may therefore have potential as a novel treatment for this disease that may result in blindness. [ABSTRACT FROM AUTHOR]

In this study, we aimed at investigating the association between glutathione- S-transferase (GSTM1 and GSTT1) deletion genotypes and susceptibility to non-arteritic anterior ischemic optic neuropathy (NAION). We hope our findings may contribute to the understanding NAION pathogenesis and provide some clues for the prevention and treatment of optic diseases. The NAION group contains 113 subjects (33 males and 80 females, mean age 55.3 ± 9.8). And 98 subjects were enrolled in the control group (32 males and 66 females, mean age 56.7 ± 10.2). The individuals involved in the study were matched by gender and age to obtain two homogenous groups. GSTM1− and GSTT1− genotype and the combined genotype were investigated. The genotype distributions in NAION patients were compared with those in the controls. Significantly altered intraocular pressure (IOP) and cup-to-disc ratio (CDR) was detected between NAION patients and controls. An increased risk of NAION was observed among individuals with GSTM1− ( P < 0.001). No significant difference was confirmed for GSTT1− ( P = 0.290). Individuals with GSTM1−/GSTT1− have a higher susceptibility to NAION ( P < 0.001); the GSTM1−/GSTT1+ genotype also had a significantly higher frequency in patients than in controls ( P = 0.004). But the genotype of GSTM1+/GSTT1− seems to have no connection with NAION ( P = 0.476). In conclusion, in this study, we confirmed the connection between NAION and GSTM1− genotype. But no significant association was observed between GSTT1− genotype and NAION susceptibility. In further analysis regarding combined genotype, a trend of protective effect was detected for GSTT1+ genotype. It is indicated by our result that oxidative compounds might play an important part in the pathogenesis of NAION. [ABSTRACT FROM AUTHOR]

A facile colloidal synthesis of CuInGaSe (CIGS) nanocrystals was successfully performed using a simple heating method. These nanocrystals were prepared by employing glycerol as a main solvent and oleylamine (OLA) as a complexing agent. X-ray diffraction showed that CuInSe with a chalcopyrite structure was formed by using a volume content of OLA as small as ~30 %. No variation was found in the compound phase between samples synthesized in a mixed solvent with 30 % OLA and in 100 % OLA-added solvent. Transmission election microscopy confirmed the crystal structure and showed a particle sizes below 20 nm. Energy-dispersive X-ray analysis (EDS) confirmed the chemical composition of these samples. And UV-Vis spectroscopy investigated the band gap of CIGS nanoinks. Furthermore, we used this method to prepare CIGS nanocrystals with different band gap energies by varying the In/Ga ratio of the reactants. Therefore, this green and economic route proposed has the potential for large-scale synthesis of CIGS nanocrystals, which is beneficial to low-cost photovoltaic application. Graphical abstract: XRD patterns and TEM images of CuInSe nanocrystals, obtained for samples synthesized with pure OLA and with mixed solvent.[Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The purpose of the present study was to determine the best cholinergic neuronal differentiation method of rhesus monkey bone marrow mesenchymal stem cells (BMSCs). Four methods were used to induce differentiation, and the groups were assigned accordingly: basal inducing group (culture media, bFGF, and forskolin); SHH inducing group (SHH, inducing group); RA inducing group (RA, basal inducing group); and SHH+RA inducing group (SHH, RA, and basal inducing group). All groups displayed neuronal morphology and increased expression of nestin and neuron-specific enolase. The basal inducing group did not express synapsin, and cells from the SHH inducing group did not exhibit neuronal resting membrane potential. In contrast, results demonstrated that BMSCs from the RA and SHH+RA inducing groups exhibited neuronal resting membrane potential, and cells from the SHH+RA inducing group expressed higher levels of synapsin and acetylcholine. In conclusion, the induction of cholinergic differentiation through SHH+RA was determined to be superior to the other methods. [ABSTRACT FROM AUTHOR]