RESUMEN
Magnetic-responsive surfactants are considered promising smart lubricating materials due to their significant stimulation response to applied magnetic fields. In this study, four magneto-responsive surfactants are successfully fabricated and encapsulated on the surface of molybdenum disulfide nanosheets (MoS2@C18H37N+(CH3)3[XCl3Br]-, X = Fe, Ce, Gd, and Ho) as base-oil components using electrostatic self-assembly, thereby constructing a multi-functional magnetic lubrication system (MoS2@STAX). Magnetorheological measurements confirm the remarkable responsiveness of MoS2@STACe lubricants at high shear rates and applied magnetic fields, which is further corroborated by the constant proximity of the magnet. The formation of dense carbon and tribo-chemical films between the friction interfaces at elevated temperatures is the primary factor contributing to the significant reduction in frictional wear. Notably, the magnetic lubricant demonstrates a pronounced response behavior when subjected to an applied magnetic field in the ceramic tribopair, even at lower magnetic fields. This work presents concepts for the development of high-temperature resistant and tunable lubrication additives by designing the material structure and controlling the magnetic stimulation.
RESUMEN
Chemoresistance challenges the clinical treatment of colorectal cancer and requires an urgent solution. Isocitrate dehydrogenase 1 (IDH1) is a key enzyme involved in glucose metabolism that mediates the malignant transformation of tumors. However, the mechanisms by which IDH1 is involved in colorectal cancer cell proliferation and drug resistance induction remain unclear. In this study, we found that IDH1 was highly expressed in human colorectal cancer tissues and could be used to indicate a high-grade tumor. In vitro gene overexpression and knockdown were used to determine whether IDH1 promoted the proliferation of the colorectal cancer cell line HCT8 and resistance to 5-Fluorouracil (5FU). Further studies have shown that the 5FU-resistant cell line, HCT8FU, secreted exosomes that contained a high level of IDH1 protein. The exosomal IDH1 derived from 5FU-resistant cells enhanced the resistance of 5FU-sensitive cells. Metabolic assays revealed that exosomes derived from 5FU-resistant cells promoted a decrease in the level of IDH1-mediated NADPH, which is associated with the development of 5FU resistance in colorectal cancer cells. Therefore, exosomal IDH1 may be the transmitter and driver of chemoresistance in colorectal cancer and a potential chemotherapy target.