Radiation therapy is a relatively effective therapeutic method for localized prostate cancer （PCa） patients. However, radioresistance occurs in nearly 30% of patients treated with potentially curative doses. Therape...Radiation therapy is a relatively effective therapeutic method for localized prostate cancer （PCa） patients. However, radioresistance occurs in nearly 30% of patients treated with potentially curative doses. Therapeutic synergy between radiotherapy and androgen ablation treatment provides a promising strategy for improving the clinical outcome. Accordingly, the androgen deprivation-induced signaling pathway may also mediate radiosensitivity in PCa cells. The C4-2 cell line was derived from the androgen-sensitive LNCaP parent line under androgen-depleted condition and had acquired androgen-refractory characteristics. In our study, the response to radiation was evaluated in both LNCaP and C4-2. Results showed that C4-2 cells were more likely to survive from irradiation and appeared more aggressive in their resistance to radiation treatment compared with LNCaP, as measured by clonogenic assays and cell viability and cell cycle analyses. Gene expression analyses revealed that a set of genes involved in cell cycle arrest and DNA repair were differentially regulated in LNCaP and C4-2 in response to radiation, which was also consistent with the radiation-resistant property observed in C4-2 cells. These results strongly suggested that the radiation-resistant property may develop with progression of PCa to androgen- independent status. Not only can the LNCaP and C4-2 PCa progression model be applied for investigating androgen-refractory progression, but it can also be used to explore the development of radiation resistance in PCa.展开更多
A new heat resisting phenol-starch moulding material (PF2C4) was prepared.Its typical raw materials formulation, preparative technology and moulding technology were determined.The method of its quatity control was put...A new heat resisting phenol-starch moulding material (PF2C4) was prepared.Its typical raw materials formulation, preparative technology and moulding technology were determined.The method of its quatity control was put forward and its properties and economic advantage were analyzed. The results show that typical raw materials formulation(mass percent)of the product is phenol-starch is phenol starch resin∶hexamethylene-tetramine∶wood flour∶calcium carbonate∶magnesium oxide∶zinc stearate∶stearic acid∶Oil Aniline Black∶ultramarine=37.0∶6.4∶30.0∶24.0∶0.6∶0.6∶0.4∶0.5∶0.5.The preparative technological parameters of the product were mixed time ≥60?min, temperature of the working roller 90—100?℃, temperature of the idle roller 145—155?℃, distance of the two rollers 2.0—2.5?mm, warm-up time 4—5?min.combining batch time≥45?min.The moulding, technological parameters of the product were preheating temperature 100—110?℃, preheating time 10—15?min, moulding pressure≥25?MPa, moulding temperature 180—185?℃, moulding time 0.8—1.0?min·mm -1 , exhaust ≥3 times. The quality of the product was controlled by bright outward appearance of sheet material of moulding material and Raschig flow property 80—120?mm of moulding material.The properties of the product came up to the national standard of raw heat resisting phenol-for maldehyde material (PF2C4), specifically its heat properties (thermal deformation temperature 174?℃) and electric properties (insulating resistance 6.0×10 12 ?Ω, dielectric strength 6.7?MV·m -1 , dielectric loss tangent 0.03)surpassed greatly the national standard.It showed very good electric properties in moist environment.By comparison with raw heat resisting thermoplastic phenol-formaldehyde moulding material(PF2C4),the cost of raw materials consumption reduced by is 20.9%.展开更多
基金This work was supported by grants fi＇om National ＂863＂ Research Program Foundation （No. 2008AA02Z123）, Key Project for drug discovery and development in China （No. 2009ZX09501-027）, and National Natural Science Foundation of China （No. 30770834 and 30870961）.
文摘Radiation therapy is a relatively effective therapeutic method for localized prostate cancer （PCa） patients. However, radioresistance occurs in nearly 30% of patients treated with potentially curative doses. Therapeutic synergy between radiotherapy and androgen ablation treatment provides a promising strategy for improving the clinical outcome. Accordingly, the androgen deprivation-induced signaling pathway may also mediate radiosensitivity in PCa cells. The C4-2 cell line was derived from the androgen-sensitive LNCaP parent line under androgen-depleted condition and had acquired androgen-refractory characteristics. In our study, the response to radiation was evaluated in both LNCaP and C4-2. Results showed that C4-2 cells were more likely to survive from irradiation and appeared more aggressive in their resistance to radiation treatment compared with LNCaP, as measured by clonogenic assays and cell viability and cell cycle analyses. Gene expression analyses revealed that a set of genes involved in cell cycle arrest and DNA repair were differentially regulated in LNCaP and C4-2 in response to radiation, which was also consistent with the radiation-resistant property observed in C4-2 cells. These results strongly suggested that the radiation-resistant property may develop with progression of PCa to androgen- independent status. Not only can the LNCaP and C4-2 PCa progression model be applied for investigating androgen-refractory progression, but it can also be used to explore the development of radiation resistance in PCa.
文摘A new heat resisting phenol-starch moulding material (PF2C4) was prepared.Its typical raw materials formulation, preparative technology and moulding technology were determined.The method of its quatity control was put forward and its properties and economic advantage were analyzed. The results show that typical raw materials formulation(mass percent)of the product is phenol-starch is phenol starch resin∶hexamethylene-tetramine∶wood flour∶calcium carbonate∶magnesium oxide∶zinc stearate∶stearic acid∶Oil Aniline Black∶ultramarine=37.0∶6.4∶30.0∶24.0∶0.6∶0.6∶0.4∶0.5∶0.5.The preparative technological parameters of the product were mixed time ≥60?min, temperature of the working roller 90—100?℃, temperature of the idle roller 145—155?℃, distance of the two rollers 2.0—2.5?mm, warm-up time 4—5?min.combining batch time≥45?min.The moulding, technological parameters of the product were preheating temperature 100—110?℃, preheating time 10—15?min, moulding pressure≥25?MPa, moulding temperature 180—185?℃, moulding time 0.8—1.0?min·mm -1 , exhaust ≥3 times. The quality of the product was controlled by bright outward appearance of sheet material of moulding material and Raschig flow property 80—120?mm of moulding material.The properties of the product came up to the national standard of raw heat resisting phenol-for maldehyde material (PF2C4), specifically its heat properties (thermal deformation temperature 174?℃) and electric properties (insulating resistance 6.0×10 12 ?Ω, dielectric strength 6.7?MV·m -1 , dielectric loss tangent 0.03)surpassed greatly the national standard.It showed very good electric properties in moist environment.By comparison with raw heat resisting thermoplastic phenol-formaldehyde moulding material(PF2C4),the cost of raw materials consumption reduced by is 20.9%.
