Background: The efficacy and safety of dexmedetomidine during the anesthesia induction of intracranial tumor patients remain unknown. We wondered whether loading infusion of dexmedetomidine 1 μg/kg over 10 min to int...Background: The efficacy and safety of dexmedetomidine during the anesthesia induction of intracranial tumor patients remain unknown. We wondered whether loading infusion of dexmedetomidine 1 μg/kg over 10 min to intracranial tumor patients was as efficient and safe as to those abdominal disease patients. Methods: Patients aged 18-60 years, male or female, ASA I or II, scheduled for intracranial tumor resection (Group N, n = 30) or abdominal operation (Group A, n = 30) were enrolled in this observational trial. Dexmedetomidine was administrated with a loading dosage of 1 μg/kg over 10 min following with continuous infusing of 0.5 μg/kg/h. Fentanyl, propofol and rocuronium were sequentially administered for anesthesia induction. Heart rate (HR), blood pressure (BP), pulse oxygen saturation (SpO2), bispectral index (BIS) and other adverse effects were recorded from the beginning of loading infusion of dexmedetomidine to the end of endotracheal intubation. Results: Among with loading infusion, HR and BIS value decreased and were significantly lower at the end of infusion than before infusion (P P > 0.05). One patient of Group N dropped out from this trial because of a serious headache. 14 of 29 patients during dexmedetomidine loading infusion suffered hypoxemia (SpO2 P Conclusion: A loading dosage of 1 μg/kg of dexmedetomidine was not suitable for the anesthesia induction of intracranial tumor patients as compared to patients undergoing abdominal operation.展开更多
Paclitaxel(PTX) is an important cancer chemotherapeutic drug. To ameliorate the disadvantages of paclitaxel, this study designed liposomes to load paclitaxel, adding the acidsensitive material cholesteryl hemisuccinat...Paclitaxel(PTX) is an important cancer chemotherapeutic drug. To ameliorate the disadvantages of paclitaxel, this study designed liposomes to load paclitaxel, adding the acidsensitive material cholesteryl hemisuccinate(CHEMS) to increase the accumulation of the drug in the tumor site. To begin, we used a high-performance liquid chromatography(HPLC)method to determine the content of PTX and the encapsulation efficiency. Then, we prepared paclitaxel-loaded acid-sensitive liposomes(PTX ASLs) by a thin-film dispersion method.We investigated the physical and chemical properties of the liposomes. The particle size was 210.8 nm, the polydispersity index(PDI) was 0.182 and the ζ-potential was-31.2 mV.The liposome shape was observed by transmission electron microscopy(TEM), and the results showed that the liposomes were round with a homogenous size distribution. The release characteristics of the liposomes in vitro were studied via a dynamic dialysis method. The results showed that the prepared liposomes had acid sensitivity and sustained release properties. An in vitro cellular uptake assay of MCF-7 cells showed that the cell uptake of coumarin-6-loaded acid-sensitive liposomes was significantly higher than that of free coumarin-6. The cytotoxicity of the PTX ASLs was significantly higher than that of paclitaxel. In conclusion,these results showed that the prepared liposomes had clear acid-sensitive release characteristics and a higher cell uptake rate and cytotoxicity than free PTX. The system is very suitable for targeted cancer therapy with paclitaxel.展开更多
文摘Background: The efficacy and safety of dexmedetomidine during the anesthesia induction of intracranial tumor patients remain unknown. We wondered whether loading infusion of dexmedetomidine 1 μg/kg over 10 min to intracranial tumor patients was as efficient and safe as to those abdominal disease patients. Methods: Patients aged 18-60 years, male or female, ASA I or II, scheduled for intracranial tumor resection (Group N, n = 30) or abdominal operation (Group A, n = 30) were enrolled in this observational trial. Dexmedetomidine was administrated with a loading dosage of 1 μg/kg over 10 min following with continuous infusing of 0.5 μg/kg/h. Fentanyl, propofol and rocuronium were sequentially administered for anesthesia induction. Heart rate (HR), blood pressure (BP), pulse oxygen saturation (SpO2), bispectral index (BIS) and other adverse effects were recorded from the beginning of loading infusion of dexmedetomidine to the end of endotracheal intubation. Results: Among with loading infusion, HR and BIS value decreased and were significantly lower at the end of infusion than before infusion (P P > 0.05). One patient of Group N dropped out from this trial because of a serious headache. 14 of 29 patients during dexmedetomidine loading infusion suffered hypoxemia (SpO2 P Conclusion: A loading dosage of 1 μg/kg of dexmedetomidine was not suitable for the anesthesia induction of intracranial tumor patients as compared to patients undergoing abdominal operation.
文摘Paclitaxel(PTX) is an important cancer chemotherapeutic drug. To ameliorate the disadvantages of paclitaxel, this study designed liposomes to load paclitaxel, adding the acidsensitive material cholesteryl hemisuccinate(CHEMS) to increase the accumulation of the drug in the tumor site. To begin, we used a high-performance liquid chromatography(HPLC)method to determine the content of PTX and the encapsulation efficiency. Then, we prepared paclitaxel-loaded acid-sensitive liposomes(PTX ASLs) by a thin-film dispersion method.We investigated the physical and chemical properties of the liposomes. The particle size was 210.8 nm, the polydispersity index(PDI) was 0.182 and the ζ-potential was-31.2 mV.The liposome shape was observed by transmission electron microscopy(TEM), and the results showed that the liposomes were round with a homogenous size distribution. The release characteristics of the liposomes in vitro were studied via a dynamic dialysis method. The results showed that the prepared liposomes had acid sensitivity and sustained release properties. An in vitro cellular uptake assay of MCF-7 cells showed that the cell uptake of coumarin-6-loaded acid-sensitive liposomes was significantly higher than that of free coumarin-6. The cytotoxicity of the PTX ASLs was significantly higher than that of paclitaxel. In conclusion,these results showed that the prepared liposomes had clear acid-sensitive release characteristics and a higher cell uptake rate and cytotoxicity than free PTX. The system is very suitable for targeted cancer therapy with paclitaxel.