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A type of Al-MCM-41 supported dual imidazolium ionic liquids were constructed and efficiently used as catalysts for the synthesis of 2-oxazolidinones from epoxides, amines, and CO2. The influence of the different catalysts and reaction parameters on the catalytic behaviours was investigated. Al-MCM-41@ILTiCl5 was identified as the most excellent catalyst because it could efficiently promote the three-component cycloaddition of CO2, epoxide, and amines to form the corresponding 2-oxazolidinones in high to excellent yields (84∼96%) with excellent selectivities (98∼99.7%). In addition, the recovery and reuse performances of Al-MCM-41@ILTiCl5 were examined. The catalyst could be recovered by simple filtration and reused six times without a change in the catalytic activity. Green reaction conditions, operational simplicity, feasibility, and sustainability of the functionalized catalyst are the main highlights of the present protocol. [ABSTRACT FROM AUTHOR]

Many kinds of drugs induce pseudo-allergic reactions due to activation of mast cells. We investigated the anti-pseudo-allergic effect of andrographolide (Andro). The effects of Andro on pseudo-allergic reactions were investigated in vivo and in vitro. Andro suppressed compound 48/80 (C48/80) induced pseudo-allergic reactions in mice in a dose-dependent manner. Andro also inhibited C48/80-induced local inflammatory reactions in mice. In vitro studies revealed that Andro reduced C48/80-induced mast cells degranulation. Human phospho-kinase array kit and western blotting showed that Andro could inhibit pseudo-allergic responses via the calcium signaling pathway. [ABSTRACT FROM AUTHOR]

Objective: Hypoxic tumor cells are more resistant to standard chemotherapies. A number of studies indicated that improving oxygenation inside the tumor could serve as a potential strategy to target hypoxia-induced chemoresistance. In this study, we examined whether a hemoglobin-based oxygen carrier (OC89) could increase tumor oxygenation and thus enhance the efficiency of transarterial chemoembolization (TACE) in an orthotopic rat HCC model. Methods: Efficiency of the hemoglobin-based oxygen carrier (OC89) in improving tumor oxygenation was examined by OxyLab pO2. Sensitization of chemotherapy (cisplatin) in TACE by OC89 was evaluated in four different therapeutic regimens including cisplatin (1 mg/kg) + OC89 (0.2 g/kg), cisplatin (1 mg/kg) + OC89 (0.4 g/kg), cisplatin (3 mg/kg) + OC89 (0.2 g/kg), cisplatin (3 mg/kg) + OC89 (0.4 g/kg). For all the therapeutic regimens, a single delivery of OC89 via the tail vein was performed 1 h before TACE. Results: Compared with Ringer's buffer, systemic delivery of OC89 (0.4 g/kg) attenuated tumor hypoxia ( p < 0.05). Additionally, partial pressure of oxygen (pO2) fraction of low readings (0-10 mmHg) inside the tumor decreased from 74.1% to 24.6% after OC89 delivery, while pO2 fraction of high readings (15-25 mmHg) increased from 22.2% to 41.5%. When cisplatin was combined with OC89, regimen cisplatin (3 mg/kg) + OC89 (0.4 g/kg) resulted in a significant inhibition of tumor growth at Day 21 after therapy ( p < 0.05). Further investigation indicated that OC89 delivery influenced anti-apoptotic and pro-apoptotic balance of the UPR pathway in the tumor. Conclusions: Our data suggest that targeting tumor hypoxia with the hemoglobin-based O2 carrier serves as a promising approach to enhance the efficacy of cisplatin-based chemotherapy in HCC. [ABSTRACT FROM AUTHOR]