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Background and Purpose: The damage or apoptosis of retinal ganglion cells (RGCs) is one of the leading causes of various blinding eye diseases, such as glaucoma, diabetic retinopathy, optic neuritis, and ischemic optic neuropathy. Oxidative stress is involved in RGCs death. Baicalin, a flavonoid compound extracted from Scutellaria baicalensis, has various beneficial effects, including anti-inflammatory, anti-apoptotic, and antioxidant properties. However, the effects of baicalin on RGCs and the underlying mechanisms require further investigation. Methods: In this study, a glutamate-induced oxidative stress damage model of R28 cells and a rat retinal injury model were established to investigate the effects of baicalin on oxidative stress damage to RGCs and try to elucidate the underlying mechanism. Results: In vitro experiments demonstrated that the survival rate of R28 cells after glutamate treatment dropped to 33.4%, while 10 μM baicalin significantly inhibited glutamate-induced damage in RGCs (P < 0.001) and enhanced cell viability through decreasing ROS levels, increasing antioxidant enzyme activity, and suppressing the expression of inflammatory factors iNOS, TNF-α, IL-6, and IL-1β (P < 0.001). In vivo , baicalin effectively mitigated structural damage to retinal tissue and RGCs morphology induced by glutamate, increasing the thickness of the retinal ganglion cell layer, improving RGCs density, and reducing overall retinal thinning in rats (P < 0.001) in a time- and dose-dependent effects. Mechanistic studies revealed that glutamate evaluated the phosphorylation levels of JAK/STAT, while baicalin effectively inhibited the activation of the JAK/STAT signaling pathway. Conclusion: This study confirmed that baicalin protects against glutamate-induced oxidative stress damage in RGCs. It effectively alleviates oxidative stress and inflammatory responses, reduces cell apoptosis, and improves the pathological changes in the retina of rat models of RGCs damage, thereby decreasing RGCs death. Further exploration of its mechanism revealed that baicalin effectively inhibits the JAK/STAT signaling pathway, protecting RGCs from oxidative stress damage. This provides an experimental basis for the application of baicalin in the treatment of RGCs damage. [ABSTRACT FROM AUTHOR]

A method for the preparation of nitriles from primary amides using trichloroacetonitrile and a catalytic amount of cupric acetate is described. Using this method, amides including aromatic amides, aromatic heterocyclic amides and aliphatic amides were converted into the corresponding nitriles in moderate to good yields. Trichloroacetonitrile reacted with amide in the presence of cupric acetate to form trichloroacetamide, which has been isolated and confirmed. [ABSTRACT FROM AUTHOR]

Background: Growing evidence has demonstrated the role of ambient air pollutants in driving diabetes incidence. However, epidemiological evidence linking ozone (O3) exposure to diabetes risk has been scarcely studied in Zhuang adults in China. We aimed to investigate the associations of long-term exposure to O3 with diabetes prevalence and fasting plasma glucose (FPG) and estimate the mediating role of liver enzymes in Zhuang adults. Methods: We recruited 13 843 ethnic minority adults during 2018–2019 based on a cross-sectional study covering nine districts/counties in Guangxi. Generalized linear mixed models were implemented to estimate the relationships between O3 exposure and diabetes prevalence and FPG. Mediation effect models were constructed to investigate the roles of liver enzymes in the associations of O3 exposure with diabetes prevalence and FPG. Subgroup analyses were conducted to identify potential effect modifications. Results: Long-term exposure to O3 was positively associated with diabetes prevalence and FPG levels in Zhuang adults, with an excess risk of 7.32% (95% confidence interval [CI]: 2.56%, 12.30%) and an increase of 0.047 mmol L−1 (95% CI: 0.032, 0.063) for diabetes prevalence and FPG levels, respectively, for each interquartile range (IQR, 1.18 μg m−3) increment in O3 concentrations. Alanine aminotransferase (ALT) significantly mediated 8.10% and 29.89% of the associations of O3 with FPG and diabetes prevalence, respectively, and the corresponding mediation proportions of alkaline phosphatase (ALP) were 8.48% and 30.00%. Greater adverse effects were observed in females, obese subjects, people with a low education level, rural residents, non-clean fuel users, and people with a history of stroke and hypertension in the associations of O3 exposure with diabetes prevalence and/or FPG levels (all P values for interaction < 0.05). Conclusion: Long-term exposure to O3 is related to an increased risk of diabetes, which is partially mediated by liver enzymes in Chinese Zhuang adults. Promoting clean air policies and reducing exposure to environmental pollutants should be a priority for public health policies geared toward preventing diabetes. [ABSTRACT FROM AUTHOR]

The rapid development of integrated circuits puts forward higher requirements for low dielectric constant polymers. In this study, two fluorinated benzoxazine monomers, bis‐(3,4‐dihydro‐3‐(4‐fluoro‐3‐(trifluoromethyl)phenyl)‐2H‐1,3‐benzoxazine)isopropane (BA‐ftfa) and bis‐(3,4‐dihydro‐3‐(4‐fluoro‐3‐(trifluoromethyl)phenyl)‐2H‐1,3‐benzoxazine)isoperfluoropropane (BAF‐ftfa), were successfully synthesized. Differential scanning calorimeter (DSC) was used to monitor the thermal curing behaviors of the monomers and their mixtures. Five groups of polybenzoxazine samples with different fluorine content (25% ~ 35%) were obtained by copolymerizing the two monomers with different mass ratios. The effects of fluorine content on dielectric properties were investigated and the results show that PBAF‐ftfa with the highest fluorine content has the lowest dielectric constant of 2.53 at 1 MHz. Furthermore, the results of thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA) show that all polymers possess excellent thermal stability and exhibit high glass transition temperatures over than 180°C. [ABSTRACT FROM AUTHOR]

Graphynes (GYs) are a novel type of carbon allotrope composed of sp and sp2 hybridized carbon atoms, boasting both a planar conjugated structure akin to graphene and a pore‐like configuration in three‐dimensional space. Graphdiyne (GDY), the first successfully synthesized member of GYs family, has gained much interest due to its fascinating electrochemical properties including a greater theoretical capacity, high charge mobility and advanced electronic transport properties, making it a promising material for energy storage applications for lithium‐ion and hydrogen storage. Various methods, including heteroatom substitution, embedding, strain, and nanomorphology control, have been employed to further enhance the energy storage performance of GDY. Despite the potential of GDY in energy storage applications, there are still challenges to overcome in scaling up mass production. This review summarizes recent progress in the synthesis and application of GDY in lithium‐ion and hydrogen storage, highlighting the obstacles faced in large‐scale commercial application of GDY‐based energy storage devices. Suggestions on possible solutions to overcome these hurdles have also been provided. Overall, the unique properties of GDY make it a promising material for energy storage applications in lithium‐ion and hydrogen storage devices. The findings presented here will inspire further development of energy storage devices utilizing GDY. [ABSTRACT FROM AUTHOR]

A method for the preparation of primary amides from nitriles using hydrogen peroxide and a catalytic amount of sodium molybdate in ethanol is described. Using this method, nitriles including aromatic nitriles, aromatic heterocyclic nitriles and aliphatic nitriles were converted into the corresponding amides in moderate to high yields. Electronic and steric effects of substituent have a significant effect on the reactivity of nitrile, nitriles with electron-withdrawing group at the para or meta position show high reactivities and they can be converted into the corresponding amide in good to high yield at room temperature. [ABSTRACT FROM AUTHOR]

Purpose. To investigate changes in corneal densitometry (CD) and visual quality following small incision lenticule extraction (SMILE) and laser epithelial keratomileusis (LASEK) in patients with mild-to-moderate myopia. Methods. A retrospective analysis was performed on 24 and 25 patients (46 eyes each) who underwent SMILE and LASEK, respectively, for mild-to-moderate myopia. The visual quality and CD values were recorded. Using the Pentacam Scheimpflug system, CD values were collected in three concentric optical zones at the depths of the anterior, central, and posterior layers. Efficacy, safety, predictability, corneal wavefront aberrations, and QoV scores were measured to evaluate visual quality. A correlation analysis was performed between changes in CD and clinical characteristics. Results. There were no statistical differences in efficacy and safety indices between the two groups. At 3 months postoperatively, a pronounced reduction in several zones was observed in the LASEK group (p < 0.05), whereas no obvious change was observed in the SMILE group. There were obvious changes in the CD values in several zones in the SMILE and LASEK groups (p < 0.05) after 1 year. The magnitude of the CD changes in the anterior and central corneal layers was smaller in the SMILE group than in the LASEK group (all p < 0.05). Lower HOAs, spherical aberration, and horizontal comas of the anterior and whole corneal surfaces were observed in the SMILE group. QoV scores were similar between the two groups. Conclusion. CD decreased in the SMILE and LASEK groups after 1 year; there was a smaller reduction in SMILE than in LASEK. SMILE and LASEK did not differ significantly in terms of safety and effectiveness in correcting mild-to-moderate myopia. [ABSTRACT FROM AUTHOR]