基于响应面法优选美洲大蠊口腔原位温敏凝胶的制备研究

目的制备美洲大蠊Periplaneta americana口腔原位温敏凝胶。方法采用自由基聚合法首次以N-异丙基丙烯酰胺(NNIPAM)和甲基丙烯酸羟丙酯(HPMA)合成聚(N-异丙基丙烯酰胺-甲基丙烯酸羟丙酯)[P(NNIPAM-HPMA)]作为温敏材料;通过冷溶法制备美洲大蠊口腔原位温敏凝胶,采用Box-Behnken设计响应面法,以溶蚀时间、胶凝时间为评价指标,在固定美洲大蠊提取物用量基础上,对羟丙基甲基纤维素(HPMC)、聚乙烯吡咯烷酮(PVP K30)、P(NNIPAM-HPMA)的用量进行优选。结果通过原位聚合法合成了P(NNIPAM-HPMA)温敏材料;并用响应面法优选了可用于口腔的美洲大蠊原位温敏凝胶的处方,优选的处方为美洲大蠊提取物10%、HPMC 3.0%、PVP K30 9.5%、P(NNIPAM-HPMA) 10.0%,其溶蚀时间为2 h,胶凝时间8～9 s。结论优选得到美洲大蠊口腔原位温敏凝胶,为美洲大蠊提取物的口腔原位局部的临床应用奠定了科学依据。     

The effects of acrylamide and Vitamin E administration during pregnancy on adult rats testis

Thirty rats, with confirmed pregnancies by vaginal smear, were divided into five groups, each including six rats, as the Control, Corn Oil, Vitamin E, Acrylamide, Vitamin E + Acrylamide groups. The births were monitored on the 21st day to select the male rats, and the selected male rats were decapitated at the end of the 8th week. Oxidant–antioxidant parameters, serum hormone levels and histopathological examinations were performed on testis tissues of the rats. It was found that acrylamide (AA) negatively affected the serum hormone levels (Total Testosterone, Progesterone, FSH, LH, Estradiol), oxidant–antioxidant parameters in the tissues (MDA, GSH, NO, SOD, CAT, TAS, TOS) (p < 0.05) and the histological findings (the Johnson's score, seminiferous tubule diameter, histopathological images), and Vitamin E administration resulted with an increase in the total testosterone, progesterone, FSH, LH, GSH, TAS, NO, SOD, CAT levels (p < 0.05) and an improvement in histopathological findings. Currently, it is almost inevitable to be exposed to food‐induced AA toxicity and such toxicity is likely to cause lifelong damage. It was concluded that Vitamin E was able to present a protective effect in the testis tissue against AA toxicity; however, further studies are necessary.     

桑色素-Cu2+配位分子印迹聚合物制备及其固相萃取应用

目的 制备桑色素-Cu²⁺配位分子印迹聚合物，对桑枝中桑色素进行分离富集。方法 在Cu²⁺存在下，丙烯酰胺为功能单体，在水-甲醇极性溶剂中制备桑色素-Cu²⁺配位分子印迹聚合物，以该聚合物为填料固相萃取桑枝中桑色素。结果 所制备配位分子印迹聚合物对桑色素具有较强的特异性、选择性吸附，最大吸附量82 μmol/g，远大于以氢键为作用力的传统印迹聚合物及非印迹聚合物；对桑色素结构类似物大豆素、儿茶素的分离因子分别为4.81、4.02。对比桑枝固相萃取淋洗液、洗脱液组成，所制备配位印迹聚合物对桑枝中桑色素表现出明显的富集效果。结论 制备的桑色素配位分子印迹聚合物环境适应性好，选择性吸附能力强，是适用于天然产物有效成分桑色素分离富集的良好材料。     

Acrylamide exposure impairs blood-cerebrospinal fluid barrier function

Previous studies show that chronic acrylamide exposure leads to central and peripheral neu- ropathy. However, the underlying mechanisms remained unclear. In this study, we examined the permeability of the blood-cerebrospinal fluid barrier, and its ability to secrete transthyretin and transport leptin of rats exposed to acrylamide for 7, 14, 21 or 28 days. Transthyretin levels in cerebrospinal fluid began to decline on day 7 after acrylamide exposure. The sodium fluorescein level in cerebrospinal fluid was increased on day 14 after exposure. Evans blue concentration in cerebrospinal fluid was increased and the cerebrospinal fluid/serum leptin ratio was decreased on days 21 and 28 after exposure. In comparison, the cerebrospinal fluid/serum albumin ratio was increased on day 28 after exposure. Our findings show that acrylamide exposure damages the blood-cerebrospinal fluid barrier and impairs secretory and transport functions. These changes may underlie acrylamide-induced neurotoxicity.     

褪黑素对丙烯酰胺大鼠神经毒性拮抗作用

目的探讨褪黑素(MT)同时干预对丙烯酰胺(ACR)神经毒性作用的影响。方法 40只SD雄性大鼠按体重随机分为4组,每组10只,分别为对照组、丙烯酰胺、褪黑素与褪黑素干预组,丙烯酰胺2.3 mmol/L溶液日常饮用;褪黑素腹腔注射2.5 mg/kg1,次/d,连续9周。每周进行步态评分,试验结束后取出大脑、小脑检测抗氧化指标。结果与对照组比较,丙烯酰胺组与褪黑素干预组第3周开始步态分值明显升高,丙烯酰胺组大脑皮层SOD活性降低9.89%,小脑SOD活性、GSH含量分别降低7.49%1、2.31%,差异均有统计学意义(P<0.05);与丙烯酰胺组比较,褪黑素干预组第4、5周步态分值分别下降22.92%、15.85%,大脑皮层SOD活性升高14.96%,差异均有统计学意义(P<0.05)。结论丙烯酰胺能导致大鼠步态改变,脑组织SOD活性及GSH含量降低。褪黑素对丙烯酰胺毒性早期有一定缓解作用,后期不明显。     

Genotoxicity studies of glycidol fatty acid ester (glycidol linoleate) and glycidol

Glycidol fatty acid esters (GEs) are found in refined edible oils. Safety concerns have been alleged due to the possible release of glycidol (G), an animal carcinogen.     

A New Method for in Vitro Calcification Using Acrylamide Gel and Bovine Serum

To investigate the mechanism of biological calcification in vitro a model system consisting of an acrylamide gel block (1×3×3 mm) and fetal bovine serum was developed. Mineral deposition was induced in gel blocks which were immersed in 300 μl of fetal bovine serum at 37°C for 7 days in a CO₂ incubator. X-ray diffraction indicated that the mineral was hydroxyapatite with low crystallinity. Effects of the concentration of acrylamide gel, the partial pressure of CO₂ and matrix proteins within the gel on the mineral formation were investigated. In the gel concentration range of 10–60%, the largest amount of crystal grew in 40% acrylamide gel, where the serum protein did not penetrate. With an increase in the partial pressure of CO₂ the Ca content in the gel block increased, reached the highest level at about 3.5% CO₂ and then began to decrease. In 40% gel and at 5% CO₂ the mineral formation was enhanced by phosvitin, phosphophoryn, demineralized dentin powder and alkaline phosphatase. Mineral deposition occurred around the collagen fibers immobilized in 40% acrylamide gel. These results indicate that 1) a putatively serum-derived inhibitor of calcification with high-molecular weight was prevented from penetrating into the 40% acrylamide gels, 2) immobilized polyanionic proteins and alkaline phosphatase were able to increase mineral deposition and 3) the partial pressure of CO₂ greatly influenced the mineral deposition. It was concluded that this gel system is useful to investigate the mechanism of biological calcification in vitro.     

Design,synthesis, and cytotoxic evaluation of novel scopoletin derivatives

A series of scopoletin derivatives were designed and synthesized by introducing α‐aminoacetamide, acrylamide and β‐aminopropamide, respectively, to 3‐position of scopoletin, and their chemical structures were confirmed by ESI‐MS, IR, ¹H NMR, and ¹³C NMR spectra. All target compounds were evaluated in vitro against four human cancer cell lines (MDA‐MB‐231, MCF‐7, HepG2, and A549) by MTT method. Cytotoxic assay showed that compounds 7a , 7b , 7e , 7f , 8a , and 8e exhibited more potent cytotoxicities compared to scopoletin. Besides, we have further evaluated the growth inhibitory activities of these selected compounds against normal tissue cell lines HFL‐1. Although compound 8a showed the strongest antiproliferative activity in vitro, it exhibited strong cytotoxicity on normal cells HFL‐1, which limited its further study. Compound 7a and 7b exhibited higher antiproliferative activity against MDA‐MB‐231 and HepG2 cells and weak cytotoxicity on HFL‐1, which suggested that 7a and 7b might be ideal anticancer candidates. The SARs showed that the introduction of the acrylamide and its analogues β‐aminopropamide could significantly improve activity, while the α‐aminoacetamide failed to enhance potency obviously. Therefore, the mechanism of compound 7a and 7b is worthy of further research and the structure of compound 8a should be further optimized.     

母源性丙烯酰胺暴露对子代鼠皮质神经元MAP-2与氧化应激的影响

目的:探讨母源性丙烯酰胺(acrylamide,ACR)暴露对子代鼠大脑皮质神经元MAP-2与氧化应激的影响。方法:SD孕鼠随机分为4组,自怀孕第6 d至怀孕第19 d起对照组和实验组分别灌胃给药给予双蒸水和每日8,16和24 mg/kg ACR溶液。HE和尼氏染色观察子代鼠皮质神经元形态学改变,免疫组织化学和Western Blot检测子代鼠皮质神经元MAP-2的表达,应用试剂盒检测大脑皮质组织中氧化应激指标丙二醛(MDA)、总超氧化物歧化酶(T-SOD)、还原谷胱甘肽(GSH)。结果:(1)MAP-2表达:与对照组相比,实验组中、高剂量组MAP-2表达下降,差异有统计学意义(P0.05),而低剂量组则差异不显著(P0.05)。(2)氧化应激指标变化:与对照组相比,实验组中、高剂量组子代鼠大脑皮质组织中MDA含量显著升高,而T-SOD活力和GSH含量显著下降,差异具有统计学意义(P0.05)。结论:丙烯酰胺致子代鼠神经元损伤的机制可能与其诱导氧化应激损伤有关。     

表没食子儿茶素没食子酸酯对丙烯酰胺致小脑颗粒神经元氧化损伤的防护作用研究

目的探讨表没食子儿茶素没食子酸酯(EGCG)对丙烯酰胺(ACR)致小脑颗粒神经元(CGNs)损伤的保护作用。方法采用体外细胞培养的方法,建立ACR损伤CGNs的体外模型。经不同浓度EGCG(5、10、25、50、100 mol/L)预处理24h后,加入ACR(5 mmol/L)染毒,24 h后用四甲基偶氮唑盐(MTT)比色法检测细胞存活率,倒置显微镜下观察细胞形态学变化,测定细胞内超氧化物歧化酶(SOD)活性及丙二醛(MDA)的含量,Hochest 33342染色观察凋亡时细胞核形态的变化,末端脱氧核苷酸转移酶介导的原位缺口末端标记(TUNEL)法检测细胞凋亡指数。结果同ACR损伤组比较,终浓度为10、25、50 mol/L的EGCG能减轻ACR引起的CGNs损伤,可明显提高细胞的存活率(P<0.05),SOD活性增高,MDA含量降低(P<0.05),Hoechst33342染色和TUNEL荧光标记显示,细胞核固缩、致密浓染现象较ACR损伤模型组改善明显,凋亡指数下降(P<0.05),且呈现剂量依赖趋势,而终浓度为5、100 mol/L EGCG组较正常组无明显变化。结论 EGCG在一定剂量范围内对ACR氧化损伤的CGNs有防护作用。[营养学报,2012,34(4):362-367]