To design an accelerated method to evaluate thymopentin release from PLGA microspheres in vitro. Microspheres were prepared by double emulsion technique, using poly(lactide-co-glycolide) (PLGA) as carrier. At high...To design an accelerated method to evaluate thymopentin release from PLGA microspheres in vitro. Microspheres were prepared by double emulsion technique, using poly(lactide-co-glycolide) (PLGA) as carrier. At higher medium temperature (45℃, 50℃ and 55℃), an accelerated release testing in short time was studied and correlated with the conventional release (37℃) in vitro. The release in vitro of thymopentin from PLGA microspheres at 45 ℃, 50℃ and 55℃ was significantly accelerated (P 〈 0.05). In particular, at 50℃, an accelerated release (30 h) of the hydrophilic peptide from the PLGA matrix was achieved and correlated well with the conventional release (30 d). An accelerated release testing in vitro at higher temperature could be used to monitor thymopentin release from PLGA microspheres.展开更多
Objection: To study the relationship between different doses and biological effect of 32p-glass microspheres (32P-GMS) by percutaneous intra-tumor injection at different times and provide proofs of theory for clini...Objection: To study the relationship between different doses and biological effect of 32p-glass microspheres (32P-GMS) by percutaneous intra-tumor injection at different times and provide proofs of theory for clinical therapy. Methods: 36 Zealand rabbits and Vx-2 were used to establish the animal model of liver tumor. Six groups were randomly designed. The suspension of different radiative doses of 32p-GMS combined with lipiodol-ultrafluid (0.1 mL) was respectively injected by percutaneous intra-tumor. The tumor tissues were examined by light microscope. MRI examination of liver tumors were performed before and after the injection. Results: C and D groups were observed that the tumor volume was decreased and the rate of restrained tumor was gradually increased after injection of 32p-GMS. The living tumor tissues of E group completely disappeared after the injection for two weeks. MRI examination showed that the tumor signal of E group was equal as T2 as the signal of normal liver parenchyma. The living tumor tissues were not found in F group after the injection for three weeks. Conclusion: 111 MBq was the best radiative dose of ~2p-GMS for treatment of 1 cm liver cancer by percutaneous intra-tumor injection. MRI examination was very valuable to evaluate the result and follow up after the injection to treat liver cancer.展开更多
To fabricate thick-walled hollow glass microspheres (HGMs) for inertial confinement fusion (ICF) targets by sol-gel technology, we investigated the effects of glass composition, blowing agent, refining temperature...To fabricate thick-walled hollow glass microspheres (HGMs) for inertial confinement fusion (ICF) targets by sol-gel technology, we investigated the effects of glass composition, blowing agent, refining temperature, pressure and composition of furnace atmosphere on the wall thickness of HGMs by numerical simulation and experiments. The results showed that the residence times of the thick-walled HGMs in the encapsulating and refining phases decreased with the increase of wall thickness of HGMs. As a response to this challenge, glass composition must be optimized with the object of high surface tension and low viscosity at refining temperature, and the blowing agents with high decomposition temperature should be used, furthermore the concentration of blowing agents in gel particles must also be precisely controlled. The higher volume fraction of argon gas in the furnace atmosphere, the thicker the wall of HGMs. Due to the limited operating range of furnace atmosphere pressure, changing furnace atmosphere pressure could not significantly increase the wall thickness of HGMs. Although increasing refin- ing temperature can improve the yield of high quality HGMs, a higher furnace atmosphere temperature may lead to a decrease in the wall thickness of HGMs. When the volume fraction of argon gas in the furnace atmosphere ranged from 80% to 95%, the furnace atmosphere pressure ranged from 1.0×l0^5 Pa to 1.25×105 Pa, and the refining temperature ranged from 1600℃ to 1800℃, we produced thick-walled (5-10 ktrn) HGMs with good sphericity, wall thickness uniformity and surface finish. However, the yield of high quality HGMs needs to be further improved. The compressive strength, tensile strength and permeation coefficient to deuterium gas of thick-walled HGMs at ambient temperature decreased with increase of the wall thickness.展开更多
文摘To design an accelerated method to evaluate thymopentin release from PLGA microspheres in vitro. Microspheres were prepared by double emulsion technique, using poly(lactide-co-glycolide) (PLGA) as carrier. At higher medium temperature (45℃, 50℃ and 55℃), an accelerated release testing in short time was studied and correlated with the conventional release (37℃) in vitro. The release in vitro of thymopentin from PLGA microspheres at 45 ℃, 50℃ and 55℃ was significantly accelerated (P 〈 0.05). In particular, at 50℃, an accelerated release (30 h) of the hydrophilic peptide from the PLGA matrix was achieved and correlated well with the conventional release (30 d). An accelerated release testing in vitro at higher temperature could be used to monitor thymopentin release from PLGA microspheres.
基金a grant from the Tianjin Municipal Commission of Science and Technology(No.003607111)
文摘Objection: To study the relationship between different doses and biological effect of 32p-glass microspheres (32P-GMS) by percutaneous intra-tumor injection at different times and provide proofs of theory for clinical therapy. Methods: 36 Zealand rabbits and Vx-2 were used to establish the animal model of liver tumor. Six groups were randomly designed. The suspension of different radiative doses of 32p-GMS combined with lipiodol-ultrafluid (0.1 mL) was respectively injected by percutaneous intra-tumor. The tumor tissues were examined by light microscope. MRI examination of liver tumors were performed before and after the injection. Results: C and D groups were observed that the tumor volume was decreased and the rate of restrained tumor was gradually increased after injection of 32p-GMS. The living tumor tissues of E group completely disappeared after the injection for two weeks. MRI examination showed that the tumor signal of E group was equal as T2 as the signal of normal liver parenchyma. The living tumor tissues were not found in F group after the injection for three weeks. Conclusion: 111 MBq was the best radiative dose of ~2p-GMS for treatment of 1 cm liver cancer by percutaneous intra-tumor injection. MRI examination was very valuable to evaluate the result and follow up after the injection to treat liver cancer.
基金supported by the Chinese Key Laboratory of Science and Technology for Defense(Grant No.91400C680603090C68)
文摘To fabricate thick-walled hollow glass microspheres (HGMs) for inertial confinement fusion (ICF) targets by sol-gel technology, we investigated the effects of glass composition, blowing agent, refining temperature, pressure and composition of furnace atmosphere on the wall thickness of HGMs by numerical simulation and experiments. The results showed that the residence times of the thick-walled HGMs in the encapsulating and refining phases decreased with the increase of wall thickness of HGMs. As a response to this challenge, glass composition must be optimized with the object of high surface tension and low viscosity at refining temperature, and the blowing agents with high decomposition temperature should be used, furthermore the concentration of blowing agents in gel particles must also be precisely controlled. The higher volume fraction of argon gas in the furnace atmosphere, the thicker the wall of HGMs. Due to the limited operating range of furnace atmosphere pressure, changing furnace atmosphere pressure could not significantly increase the wall thickness of HGMs. Although increasing refin- ing temperature can improve the yield of high quality HGMs, a higher furnace atmosphere temperature may lead to a decrease in the wall thickness of HGMs. When the volume fraction of argon gas in the furnace atmosphere ranged from 80% to 95%, the furnace atmosphere pressure ranged from 1.0×l0^5 Pa to 1.25×105 Pa, and the refining temperature ranged from 1600℃ to 1800℃, we produced thick-walled (5-10 ktrn) HGMs with good sphericity, wall thickness uniformity and surface finish. However, the yield of high quality HGMs needs to be further improved. The compressive strength, tensile strength and permeation coefficient to deuterium gas of thick-walled HGMs at ambient temperature decreased with increase of the wall thickness.