Myocardial infarction (MI), a type of coronary heart disease, has had a significantly increased incidence in recent years. The balance of cardiomyocyte apoptosis and autophagy after MI is one of the main determinants of patient prognosis. Both affect myocardial fibrosis and ventricular remodeling and regulate cell survival. However, there are few studies on the regulation mechanism of cardiomyocyte autophagy and apoptosis in the early stage after MI. In this study, based on analyzing the scRNA-seq and mRNA-seq data of mice in the early stage of MI, we found that the expression of S100a8 and S100a9 increased first and then decreased in the early stage of MI, and their expression level changed with the number of neutrophils. Further, through the functional enrichment analysis of the differentially expressed genes, we found that S100a8 and S100a9 were simultaneously associated with autophagy and apoptosis and could regulate autophagy and apoptosis of cardiomyocytes through MAPK or PI3K-AKT signaling pathways. This study provides valuable insights for clarifying the pathogenesis of early stage MI and improving its early treatment.

The bioderived polycarbonate (ISB-PC) was synthesized via transesteri cation and polycondensation of isosorbide (ISB) and diphenyl carbonate (DPC), using lithium acetoacetone as catalyst. The resulting ISB-PC exhibited high glass transition temperatures similaring to bisphenol A polycarbonate (BPA-PC), and were thermally stable up to 350 ℃. The incorporation of isosorbitol into the polymer chain imparted an improved mechanical property of ISB-PC, such as a higher bending and tensile modulus and higher elongation at break. The ISB-PC can be readily cast into transparent lms with a tensile strength of 73.3 MPa and a tensile modulu of 534 MPa. The ISB-PC displayed a highly UV transmittance and possessed a blue uorescence under the UV irradiation. At the same time, ISB-PC also has strong anti-yellowing ability.

In this work, the antistatic effect of antistatic agent (AA) on semi-aromatic poly (decamethylene terephthalamide) (PA10T) with 30 wt.% glass fiber (GF) was investigated. The PA10T/AGF antistatic composites with excellent thermal characteristics, balanced toughness, and notched impact strength were prepared through one-step melt blending, and added the AA and GF to the PA10T matrix.Meanwhile, the structure, morphology, thermal properties, and mechanical properties were examined in detail by FT-IR, SEM, TGA, DSC, and tensile and impulse testing. The results showed that the antistatic GF dispersed well in the PA10T matrix and interacted well with the PA10T matrix. The antistatic properties increased with the increase of AA content, and AA/GF-5 composites had the best antistatic effect when AA content was 25 wt.%. However, with the increase of AA content, the melt temperature of PA10T/AGF composites decreased, while the machining performance and thermal stability of PA10T/ AGF composites increased. The composites' tensile strength and breaking elongation followed a rising and falling pattern with increasing AA concentration. Notwithstanding, the notched impact strength of PA10T/AGF composites decreased and then increased. Therefore, this work provides us with a deep understanding of the antistatic effect of AA on polymers.

In this study, WPU@SiO2 nanoparticles were obtained by grafting waterborne polyurethane (WPU) on the surface of silicon dioxide (SiO2). Then, WPU@SiO2 nanoparticles were introduced into the matrix of polybutylene succinate (PBS) to prepare a series of PBS/WPU@SiO2 composites. The dispersibility and interfacial compatibility of filler and matrix can be improved obviously by grafting a layer of WPU onto the surface of SiO2 nanoparticles. The FTIR and TGA results showed that WPU was successfully grafted onto the surface of SiO2. According to polarizing microscope images, it is clear that the size of the pure PBS crystals is much larger than that of the PBS/WPU@SiO2, and a large number of crystals are evenly distributed in the PBS/WPU@SiO2 composite. In addition, DSC and TGA results indicated that PBS/WPU@SiO2 composite films show excellent thermal properties. Meanwhile, the initial thermal decomposition temperature of PBS/WPU@SiO2 composite films is about 366–374°C. For the 10 wt% WPU@SiO2 reinforced PBS‐based composite films, the tensile strength reached the ultimate value (38.49 MPa), which is 32.04% higher than that of pure PBS. Based on its excellent mechanical and thermal properties, the PBS/WPU@SiO2 composites have a broad application prospect in the field of biodegradable materials.

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