The effect of colorant additive on the rheology of PP polymer melt and the influence of spinning conditions on the crystalline and orientation structure of mass-dyed as-spun PP filament are reported. The △E~~~ value ...The effect of colorant additive on the rheology of PP polymer melt and the influence of spinning conditions on the crystalline and orientation structure of mass-dyed as-spun PP filament are reported. The △E~~~ value for all colored chips is higher than that of blank chip to a varying degree. The crystallinity and orientation degree of dyed PP as-spun filament decrease with increasing melt temperature, decreasing spinning speed and increasing denier per filament (dpf), while the crystallinity of dyed as-spun filament increases with the content of colorant additive as a nucleation agent.展开更多
[Objectives] To explore the inhibitory effects of flavonoids from Scutellaria baicalensis Georgi stems and leaves against abnormal formation of PHF and regulation mechanism of protein phosphatase(PP) in okadaic acid(O...[Objectives] To explore the inhibitory effects of flavonoids from Scutellaria baicalensis Georgi stems and leaves against abnormal formation of PHF and regulation mechanism of protein phosphatase(PP) in okadaic acid(OA) induced brain injury in rats.[Methods]Male Sprague-Dawley rats were treated with OA(200 ng/kg) in the lateral ventricle to establish a memory impairment model,and Morris water maze was used to screen the memory impairment model.Rats were intragastrically administered with 25,50 and 100 mg/kg SSF daily for 36 d.The protein expressions of PHF,PP1,PP2A-Cα,PP2A-Cβ,PP2 CA and PP2 CB in rat cortex and hippocampus were determined by Western blot.Ginkgo biloba leaf flavonoids were used as positive control drugs.[Results]Compared with the sham-operated rats,the expression of PHF protein in the cortex and hippocampus of the model group was significantly increased(P < 0.01);protein expression of PP2A-Cα and PP2A-Cβin the cortex and hippocampus,and PP2 CB in the hippocampus were significantly decreased(P < 0.05);protein expression of PP2 CA and PP2 CB in the cortex was significantly increased(P < 0.01);protein expression of PP1 in the cortex was significantly decreased(P < 0.01).Compared with the model rats,25,50 and 100 mg/kg SSF 36 d reversed the protein expression of PHF,PP2A-Cα and PP2ACβ in rat cortex and hippocampus and expression of PP1 in rat cortex induced by OA,but had no significant effect on the protein expression of PP2 CA and PP2 CB,G.biloba flavonoids also showed similar results to SSF.[Conclusions] SSF can significantly inhibit the abnormal formation of PHF in rat brain induced by OA.The inhibitory effect may be related to the regulation of PP1,PP2A-Cα and PP2A-Cβ protein expression in cerebral cortex and hippocampus by SSF,but less related to the regulation of PP2 CA and PP2 CB.展开更多
文摘The effect of colorant additive on the rheology of PP polymer melt and the influence of spinning conditions on the crystalline and orientation structure of mass-dyed as-spun PP filament are reported. The △E~~~ value for all colored chips is higher than that of blank chip to a varying degree. The crystallinity and orientation degree of dyed PP as-spun filament decrease with increasing melt temperature, decreasing spinning speed and increasing denier per filament (dpf), while the crystallinity of dyed as-spun filament increases with the content of colorant additive as a nucleation agent.
基金Supported by Hebei Province Colleges Hundred Outstanding Innovative Talent Support Program(First Session)Key Science and Technology Project of Hebei Provincial Education Department(ZD20131022)+1 种基金Project for Key Disciplines of Traditional Chinese Medicine in Colleges and Universities of Hebei Province(Ji Jiao Gao[2013]No.4)Program of Key Development Discipline of Pharmacology of Traditional Chinese Medicine in Chengde Medical College(Cheng Yi Fa[2016]No.140)
文摘[Objectives] To explore the inhibitory effects of flavonoids from Scutellaria baicalensis Georgi stems and leaves against abnormal formation of PHF and regulation mechanism of protein phosphatase(PP) in okadaic acid(OA) induced brain injury in rats.[Methods]Male Sprague-Dawley rats were treated with OA(200 ng/kg) in the lateral ventricle to establish a memory impairment model,and Morris water maze was used to screen the memory impairment model.Rats were intragastrically administered with 25,50 and 100 mg/kg SSF daily for 36 d.The protein expressions of PHF,PP1,PP2A-Cα,PP2A-Cβ,PP2 CA and PP2 CB in rat cortex and hippocampus were determined by Western blot.Ginkgo biloba leaf flavonoids were used as positive control drugs.[Results]Compared with the sham-operated rats,the expression of PHF protein in the cortex and hippocampus of the model group was significantly increased(P < 0.01);protein expression of PP2A-Cα and PP2A-Cβin the cortex and hippocampus,and PP2 CB in the hippocampus were significantly decreased(P < 0.05);protein expression of PP2 CA and PP2 CB in the cortex was significantly increased(P < 0.01);protein expression of PP1 in the cortex was significantly decreased(P < 0.01).Compared with the model rats,25,50 and 100 mg/kg SSF 36 d reversed the protein expression of PHF,PP2A-Cα and PP2ACβ in rat cortex and hippocampus and expression of PP1 in rat cortex induced by OA,but had no significant effect on the protein expression of PP2 CA and PP2 CB,G.biloba flavonoids also showed similar results to SSF.[Conclusions] SSF can significantly inhibit the abnormal formation of PHF in rat brain induced by OA.The inhibitory effect may be related to the regulation of PP1,PP2A-Cα and PP2A-Cβ protein expression in cerebral cortex and hippocampus by SSF,but less related to the regulation of PP2 CA and PP2 CB.
