β-Cypermethrin Alleviated the Inhibitory Effect of Medium from RAW 264.7 Cells on 3T3-L1 Cell Maturation into Adipocytes

Studies have elucidated that pyrethroids induce adipogenesis. It is also known that macrophages can affect the homeostasis of adipose tissue. However, whether and how the β-cypermethrin (β-CYP)-mediated inhibition of the macrophages affects adipogenesis remain unknown. To explore the effects of β-CYP on adipogenesis through modulating the function of macrophages, 3T3-L1 cells, a preadipocyte cell line, were exposed to culture medium from either RAW 264.7 cells, a macrophage cell line (RM), or β-CYP-treated RAW 264.7 cells (CRM). CRM decreased the inhibitory effects of RM treatment on cell proliferation and adipogenesis, as lipid accumulation, the CEBPA content, and Fasn and Acaca expression in 3T3-L1 cells were higher following CRM treatment than following RM treatment through the higher levels of the demethylated CEBPA promoter in 3T3-L1 cells. However, the medium from β-CYP- and N-acetyl-L-cysteine-cotreated RAW 264.7 cells (CNRM) partially restored the inhibitory effects of RAW 264.7 cells on 3T3-L1 cells that had been reduced by CRM, indicating that β-CYP might reduce the cytotoxicity and inhibitory effects of RAW 264.7 cells on the adipogenesis of 3T3-L1 cells through elevating ROS levels in RAW 264.7 cells. Moreover, exposure to β-CYP downregulated the TNF-α secretion in RAW 264.7 cells. In conclusion, these data demonstrated that β-CYP affected the function of RAW 264.7 cells, alleviating their inhibitory effects on adipogenesis and CEBPA demethylation in 3T3-L1 cells. β-CYP might achieve these effects through downregulating the secretion of TNF-α via elevating ROS levels in RAW 264.7 cells. Our experiments provide a new perspective on the obesogenic effect of pyrethroids.     

Experimental study of neutron counting in a zero-power reactor driven by a neutron source inherent in highly enriched uranium fuels

Even a zero-power reactor core containing highly enriched uranium has a weak neutron source inherent in uranium 235, and consequently, a neutron counter placed closely to the core without external neutron source registers a certain counting rate. The study of the counting is very important for zero-power reactor physics experiments with a high precision. In this experimental study, first, at a shutdown state of the UTR-Kinki reactor without start-up neutron source, a pulse height distribution of output signals from a neutron proportional counter was measured to confirm that these signals resulted from neutron detections. At several subcritical states of the UTR, then, the Feynman-α analysis was carried out to confirm that the neutrons detected by the counter must be fission neutrons multiplied by fission chain reactions. The correlation amplitude measured in the Feynman-α analysis was much higher than that measured in a previous drive by start-up source. Further, it was also confirmed that the subcriticality dependence of neutron counting rate followed the source multiplication formula. This feature indicated that the one-point model was very successful in the subcritical range including the shutdown state.     

一种等价于PI的二型模糊控制器设计算法

区间二型模糊集合将次隶属度做了简化,基于KM降阶算法的区间二型模糊控制器实现起来相对简单.虽然区间二型模糊控制器在一定程度上优于传统的一型模糊控制器或者PI控制器等,但区间二型模糊控制器并没有充分利用二型模糊集合的次隶属度信息.为解决这些问题,研究了普通二型模糊控制器的一般结构,提出了一种等价于PI的二型模糊控制器.该...     

热处理对扇贝闭壳肌肌动球蛋白生化性质的影响

肌动球蛋白是扇贝闭壳肌中的主要功能蛋白质,对贝类制品的品质起关键的作用。文中以虾夷扇贝(Patinopecten yessoensis)闭壳肌为原料,提取其肌动球蛋白,并考察了热处理温度和时间对肌动球蛋白的α-螺旋含量、表面疏水性、活性-SH含量和浊度的影响。结果表明:在热处理过程中,扇贝闭壳肌肌动球蛋白的α-螺旋发生解旋,肽链展开,疏水性氨基酸残基暴露,蛋白表面疏水性增强;同时热处理使活性-SH氧化生成二硫键,蛋白聚集,使得扇贝闭壳肌肌动球蛋白的浊度增加。加热温度越高,这些指标变化越快。由此推断,扇贝闭壳肌肌动球蛋白在热处理过程中伴随着肽链的解旋和蛋白的无规则聚集。     

高D-α-生育酚对油脂氧化稳定性影响

用Rancimat仪测定高D-α-生育酚对油脂氧化稳定性影响,并与其它抗氧化剂进行比较分析。结果表明:高D-α-生育酚在猪油中有较强抗氧化效果,其抗氧化效果强于DL-α-生育酚,而稍弱于天然维生素E;而在大豆色拉油及葵花籽色拉油中有不太显著抗氧化效果,同时,高D-α-生育酚浓度及作用温度也对油脂氧化稳定性产生影响。     

发酵糙米的加工工艺

对用酵母发酵糙米的工艺进行研究。以糙米粉为试验材料,添加水、蜂蜜、盐、大麦芽粉为底物,采用活性酵母液进行发酵试验。以淀粉酶活力作为试验指标,设计包含培养基加水量、发酵温度、时间和接种量四个因素水平,通过正交试验确定糙米发酵培养基的最佳配方和最佳发酵条件。优化的工艺条件为加水量为150%,酵母接种量为4%,发酵温度为30℃,发酵时间为为4 h。糙米酵素中的α-淀粉酶含量最高,达到485 U/g。     

嗜热链球菌grx02对酒精性肝损伤大鼠保护作用的分子机制

研究了嗜热链球菌grx02对急性酒精性肝损伤大鼠模型的保护作用机制。建立了急性酒精性肝损伤大鼠模型,观察嗜热链球菌grx02对急性酒精性肝损伤大鼠血清转氨酶以及炎症细胞因子的改善作用。结果表明,酒精可诱导大鼠血清谷氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、丙二醛(MDA)水平显著升高,;血清、肝匀浆中肿瘤坏死因子-α(TNF-α)、白介素-1β(IL-1β)、白介素-8(IL-8)细胞因子水平显著升高;乙醇脱氢酶(ADH)、还原性谷胱甘肽(GSH)、增加谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活性显著下降,与对照组比较均有显著性差异。结论:grx02可能通过抑制炎性因子,增强抗氧化酶系活性、抑制氧化应激引发的肝损伤,对大鼠急性酒精性肝损伤发挥保护作用。     

Effect of additives on mesophilic α-amylase and its application in the desizing of cotton fabrics

An investigation was carried out on thermal stability of α-amylase. The influence of various additives (calcium acetate, sodium lactate, L-histidine, and water-soluble chitosan) on the stability of α-amylase was studied. Results showed the inactivation behavior of α-amylase with or without additives all followed the first-order kinetics. All additives (Ca2+, sodium lactate, L-histidine, and water-soluble chitosan) displayed good stabilizing effect on α-amylase lower than 80 °C, and only water-soluble chitosan had an efficient stabilizing effect on α-amylase when the treatment temperature exceeds 80 °C. All additives improved the catalytic activity of α-amylase at 70–90 °C, and the appearance of water-soluble chitosan increased the catalytic activity of α-amylase at 90 °C sharply. A desizing ratio of 68.42% was obtained by treating the cotton fabrics in the buffer solution at 100 °C without α-amylase. To obtain a desizing ratio exceed 95% when fabrics were treated at 100 °C for 10 min, the addition of water-soluble chitosan saves 2/3 α-amylase dosage. Moreover, water-soluble chitosan showed a further improvement in desizing effect than the additive of calcium acetate.     

真姬菇菌丝体发酵藜麦产物中多糖的抗氧化和α-淀粉酶抑制活性

利用真姬菇发酵藜麦,通过单因素试验优化发酵物中多糖的提取条件,并将提取的多糖进一步分离纯化,分别测定多糖纯化前后的抗氧化和α-淀粉酶抑制活性。试验结果表明:酶解辅助提取法较优,多糖提取量为(207.67±2.52)mg/g。对提取到的多糖分离纯化后得到4种多糖组分。未纯化多糖(unpurified polysaccharide,UP)对DPPH和羟基自由基清除效果较其他组分显著,最高清除率达到28.95%与43.36%;中性多糖(neutral polysaccharide,NP)对ABTS+自由基清除效果最为明显,最高值达到了51.22%。酸性多糖-0.1(acid polysaccharide-0.1,AP-0.1)对枯草芽孢杆菌来源的α-淀粉酶的抑制效果最强,最高抑制率为60.22%;酸性多糖-0.5(acid polysaccharide-0.5,AP-0.5)对猪胰腺来源的α-淀粉酶抑制能力较显著,最高抑制率为50.36%。结果表明真姬菇与藜麦发酵产物多糖具有一定的抗氧化和α-淀粉酶抑制活性,为其在功能性食品添加剂方向的应用提供了数据基础。