Porphyrin-anthracene covalent organic frameworks for sustainable photosterilization

Covalent organic frameworks (COFs) have promising applications in enhanced phototherapy. However, COFs that can sustainably play a role in phototherapy without continuous irradiation are extremely scarce. Herein, we report the fabrication of porphyrin-anthracene multifunctional COFs (Por-DPA) for sustainable photosterilization and bacterial-infected wound healing. A porphyrin photosensitizer, as one of the monomers, was used to provide photothermal and photodynamic activities under irradiation. An anthracene derivative, a good chemical source of singlet oxygen (1O2), was selected as another monomer to capture 1O2 and release it continuously via cycloreversion in the dark. The prepared Por-DPA COF prevents the self-aggregation quenching of the photosensitizer and thermal damage caused by continuous exposure to external light sources. Besides, Por-DPA exhibits good photothermal conversion performance and efficient 1O2 production capacity through dual pathways of photosensitization and cycloreversion. The developed sustainable photosterilization platform not only has good bactericidal effects on Escherichia coli and Staphylococcus aureus, but also promotes wound healing without obvious side effects, and is expected to be a novel efficient bactericide.

[Safety of del Nido cardioplegia in coronary artery bypass grafting combined with heart valve replacement in adults]

Objective: To investigate the safety and myocardial protective effect of del Nido cardioplegia in coronary artery bypass grafting combined with heart valve replacement in adults. Methods: From April 2018 to April 2019, 84 patients undergoing coronary artery bypass grafting combined with heart valve replacement under cardiopulmonary bypass (CPB) in the Second Affiliated Hospital of Nantong University and Shanghai Chest Hospital were selected, and divided into del Nido cardioplegia (n=44) group and Thomas cardioplegia (n=40) group using a random number table. The concentration of troponin was measured before anesthesia induction and 2, 12 and 24 hours after the termination of CPB, respectively. Results: The preoperative characteristics of each group were similar, including age, underlying diseases, and body surface area (all P>0.05). The frequency of intraoperative cardioplegia infusion in the del Nido group was significantly lower than that in the Thomas group (P=0.03). Compared with the del Nido group, troponin concentration in the Thomas group increased significantly at 12 hours [(4.59±0.76) μg/L vs (2.20±0.53) μg/L, t=-16.653, P<0.001] and 24 hours [(6.70±0.97) μg/L vs (1.96±0.58) μg/L, t=-26.975, P<0.001] after CPB. No statistically significant differences were found in the postoperative recovery of cardiac autonomic rhythm (P=0.887), cardiac defibrillation (P=0.880), positive inotropic drugs (P=0.163) and left ventricular ejection fraction (P=0.338) between the two groups. Conclusions: It is safe to use del Nido cardioplegia in coronary artery bypass grafting combined with heart valve replacement in adults, which can reduce the frequency of cardioplegia infusion and simplify the surgical procedure. The trend of troponin concentration suggests that del Nido cardioplegia has a better myocardial protective effect.