Effect of heat on the distribution of fluorescently labeled plasminogen and plasminogen activators in bovine skim milk

ABSTRACT:  Differentially fluorescently labeled bovine plasminogen (PG-594) and human tissue- and urokinase-type plasminogen activators (tPA-647 and uPA-546) were added to bovine skim milk to track the effect of heat on the location and concentration of these plasmin system components following acid precipitation or ultracentrifugation. In unheated milk, the majority (71.7% to 89.0%) of the added PG and PAs associated with casein micelles or acid curd, and PG-594 in the serum fraction was partially due to associations with nonsedimentable caseins. Heat treatment (85 °C for 16 s) significantly ( P < 0.05) affected distribution of PG-594, tPA-647, and uPA-546, resulting in reduced concentrations of PG and PAs in the serum fractions and reciprocal increases in their levels in the nonsedimentable casein fractions. Overall, almost all of the added PG and PAs (95.9% to 97.5%) became associated with caseins following heat treatment. This is the 1st study to successfully use fluorescent labeling to quantify effects of heat on the location of plasmin components in skim milk.     

棉织物低温氧漂稳定剂和活化剂

分别在80℃和pH值9、pH值11两种工艺条件下,对氧漂稳定剂和活化剂进行优选.试验发现,稳定剂D能够有效螯合水中的Fe3+并控制双氧水的分解;在80℃和pH值9的条件下,活化剂A有较好的促进漂白作用,最佳质量浓度为0.6×10-3g/L,稳定剂D最佳质量浓度为1g/L;在80℃和pH值11的条件下,活化剂S促进漂白作...     

多功能橡胶硫化活性剂ZH-73对全钢载重子午线轮胎胎面胶性能的影响

研究多功能橡胶硫化活性剂ZH-73对子午线轮胎胎面胶硫化特性、加工性能、物理性能和动态力学性能等的影响。结果表明:加入2份硫化活性剂ZH-73,混炼胶的门尼焦烧时间略缩短,t90延长,流动性提高,加工性能改善;硫化胶老化前后物理性能相当,60℃的损耗因子明显减小;成品轮胎耐久性能提高,滚动阻力系数降低。     

Inhibition of RANKL-Induced Osteoclastogenesis by Novel Mutant RANKL

Background: Recently, it was reported that leucine-rich repeat-containing G-protein-coupled receptor 4 (LGR4, also called GPR48) is another receptor for RANKL and was shown to compete with RANK to bind RANKL and suppress canonical RANK signaling during osteoclast differentiation. The critical role of the protein triad RANK–RANKL in osteoclastogenesis has made their binding an important target for the development of drugs against osteoporosis. In this study, point-mutations were introduced in the RANKL protein based on the crystal structure of the RANKL complex and its counterpart receptor RANK, and we investigated whether LGR4 signaling in the absence of the RANK signal could lead to the inhibition of osteoclastogenesis.; Methods: The effects of point-mutated RANKL (mRANKL-MT) on osteoclastogenesis were assessed by tartrate-resistant acid phosphatase (TRAP), resorption pit formation, quantitative real-time polymerase chain reaction (qPCR), western blot, NFATc1 nuclear translocation, micro-CT and histomorphological assay in wild type RANKL (mRANKL-WT)-induced in vitro and in vivo experimental mice model. Results: As a proof of concept, treatment with the mutant RANKL led to the stimulation of GSK-3β phosphorylation, as well as the inhibition of NFATc1 translocation, mRNA expression of TRAP and OSCAR, TRAP activity, and bone resorption, in RANKL-induced mouse models; and Conclusions: The results of our study demonstrate that the mutant RANKL can be used as a therapeutic agent for osteoporosis by inhibiting RANKL-induced osteoclastogenesis via comparative inhibition of RANKL. Moreover, the mutant RANKL was found to lack the toxic side effects of most osteoporosis treatments.     

Hierarchically porous carbon derived from the activation of waste chestnut shells by potassium bicarbonate (KHCO3) for high-performance supercapacitor electrode

3D hierarchical porous carbon consisting of micropores, mesopores and macropores was successfully prepared through the activation of chestnut shell via KHCO₃. The influence of KHCO₃/chestnut shell ratio on the textural properties was carefully investigated and the structure, micrographs, and surface chemical status of the materials were expressed via X-Ray diffraction (XRD), transmission electron micrographs (TEM), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), respectively. With the optimized amount of KHCO₃, high specific pore surface area (2298 m² g^-1) and high total pore volume (1.51 cm³ g^-1) were achieved, endowing an advantageous electrochemical characteristics for the electrode as ultracapacitors in three-electrode system. At 2 A g^-1, a high specific electric capacity of 387 F g^-1 was reached. The remarkable electrochemical performances are mainly due to hierarchical porous structure with the high specific surface area (SSA) and the eminent total pore volume. It means that this hierarchical porous carbon prepared by activated by using KHCO₃ would have more promising foreground in the field of energy storage.     

养护温度对粉煤灰基矿物聚合物强度影响的研究

研究了不同养护温度下粉煤灰基矿物聚合物的抗压强度，以及经过1d高温养护后常温条件下强度的发展特点。结果表明：提高养护温度可以提高粉煤灰基矿物聚合物的抗压强度，缩短养护时间。同时，其强度提高程度因激发剂溶液种类不同而不同，5MK2SiO3溶液的提高程度最高；其它3种激发剂的提高幅度较小，高温养护7d时的强度与常温28d时的强度接近。     

印染助剂发展的回顾与展望(续)

回顾了我国印染助剂,特别是表面活性剂的发展状况。重点介绍了前处理助剂的革新和Gemini表面活性剂及树状聚合物的合成方法、性能及应用。提出行业应注重创新,以促进我国印染助剂发展。     

Na2C2O4对硬石膏水化硬化的影响及作用机理

研究了草酸钠对硬石膏水化进程、硬化体显微结构与强度、液相离子浓度与二水石膏析晶过饱和度的影响,从二水石膏晶体成核与生长的角度探讨了草酸钠的作用机理.草酸钠使硬石膏水化率提高,水化热集中,水化潜伏期缩短,水化进程加快;草酸钠使二水石膏晶体细化,硬化体结构致密,强度提高,是硬石膏水化活性的高效激发剂.草酸钠作用机理归纳为：草酸钠与硬石膏反应形成草酸钙沉淀与可溶硫酸盐,使液相SO2-4浓度大幅提高;提高二水石膏析晶过饱和度,使二水石膏临界晶核半径减小,晶体成核与生长速率加快;草酸钠促进硬石膏溶解.     

负载型TiO2光催化剂的制备及光催化活性研究

目的 研究TiO2的光催化活性,制备可悬浮的负载型TiO2光催化剂,并以活性艳红X-3B有机染料为降解对象来检验光催化剂的光催化活性.方法 以钛酸正四丁酯为前躯体、无水乙醇为溶剂、以粒径2～3 mm粗孔硅胶微球为载体,用溶胶-凝胶法制备负载型TiO2光催化剂.以20 W(λ=253.7 nm)紫外线杀菌灯为光源,采用自制反应器进行光催化氧化试验.通过试验研究分析如负载型TiO2光催化剂无水乙醇和硝酸的投加量、镀膜次数、煅烧温度等因素对光催化降解效果的影响.结果 镀膜5次、煅烧温度为450℃制成的催化剂对活性艳红X-3B染料废水有较好的去除效果,当废水初始浓度50 mg/L,调节pH为3左右,催化剂的投加量为10 g/L,反应2 h,脱色率96%以上.结论 用溶胶一凝胶法制备负载型TiO2光催化剂具有较好的光催化活性,且克服了粉末状TiO2难回收、易流失的缺点.