转Xa21基因大米亚慢性毒性实验

目的　观察Xa2 1转基因大米对大鼠的亚慢性毒性损害。方法　将Wistar大鼠按性别体重随机分为转基因大米组、非转基因大米组和AIN93G正常对照组。分别饲相应饲料 90天 ,自由进食。观察大鼠体重、身长、血常规、血生化、脏器重量、骨密度和脏器的病理学检查。结果　与非转基因大米组相比 ,实验中期转基因大米组血糖降低 ,胆固醇和高密度脂蛋白升高 ,实验结束时上述差异消失 ,但雌性组谷草转氨酶活性显著升高。与AIN93G正常对照组相比 ,实验中期转基因大米组体重、甘油三酯、高密度脂蛋白显著增高 ,血糖降低 ;实验结束时上述差异消失。脑、心、脾、肺、肾、胃、十二指肠、肾上腺、睾丸、卵巢病理检查未见异常。结论　现有实验结果不能证实转基因大米对大鼠有亚慢性毒性作用     

Xa21转基因大米对大鼠致畸作用的实验研究

目的　观察Xa2 1转基因大米对大鼠胚胎生长、发育的影响。方法　将初断乳Wistar大鼠按雌雄分别随机分为 4组 :转基因大米组、非转基因大米组、AIN93G对照组和敌枯双阳性对照组。单笼喂养 ,饲相应鼠料 ,喂满 90天 ,雌雄合笼。观察母鼠和胎鼠的生长发育情况。结果　转基因大米组孕鼠增重、活胎体重、身长、尾长均显著高于阳性对照组 ,而死胎数、吸收胎数、畸形率 (外观、内脏、骨骼 )均显著低于阳性对照组。转基因大米组与非转基因大米组、AIN93G对照组相比 ,所有观察指标均无统计学差异。结论　转Xa2 1基因大米与非转基因大米相比 ,对大鼠受孕率、胚胎生长发育无显著性差异。     

转基因大米的免疫毒理学评价

目的　评价转基因大米和非转基因大米对小鼠免疫功能的异同。方法　以转豇豆胰蛋白酶抑制剂 (cowpeatrypsininhibitor ,CpTI)基因大米和母系非转基因大米喂养BALB C小鼠 30天 (均配成AIN 93G的全价营养饲料 ,并且含有最大量的转基因大米或非转基因大米 ) ,比较各组小鼠的各项免疫毒理指标 :体重、脏器指数、血常规、淋巴细胞分类、血清抗体滴度、空斑试验 (PFC)、迟发型皮肤过敏反应 (DTH)、腹腔巨噬细胞吞噬鸡红细胞试验。结果　发现转基因大米和非转基因大米喂养的小鼠各项免疫毒理指标无差异。结论　转基因大米对小鼠的免疫功能的影响与非转基因大米基本相同 ,转基因大米与非转基因大米在免疫毒理学方面的评价具有“实质等同性”。     

转豇豆胰蛋白酶抑制剂大米的致畸作用研究

目的　用表达杀虫蛋白CpTI(豇豆胰蛋白酶抑制剂 )的大米喂养Wistar大鼠 ,研究其是否具有致畸作用。方法　将断乳的Wistar大鼠随机分为 4组 ,转基因大米组、非转基因大米组、阴性对照组和阳性对照组 ,敌枯双为阳性对照物。转基因大米组含 78 3%转基因大米 ,非转基因大米组含 74 7%与转基因大米同品系的非转基因大米 ,两个对照组的饲料为AIN93G ,三种饲料的宏量及微量营养素的含量相同。大鼠性成熟后 ,进行传统的致畸实验 ,观察母鼠及胎鼠的情况。结果　转基因大米组的孕鼠增重、胎鼠体重、身长和尾长显著高阳性对照组 ,畸形率 (包括外观畸形、骨骼畸形和内脏畸形 )显著低于阳性对照组 (P <0 0 1) ,转基因大米组、非转基因大米组及阴性对照组间的所有指标均无显著性差异 (P >0 0 5 )。结论　此种转CpTI基因的大米对大鼠无母体毒性、胚胎毒性和致畸作用。     

不同品种早稻糙米蛋白质和氨基酸组成研究

目的:研究安徽省12个品种早稻糙米的蛋白质和氨基酸含量及其组成特性。方法:通过化学分析评价不同品种早稻糙米蛋白质的营养价值。结果:12种早稻糙米蛋白质含量平均为9.19%,其中谷蛋白占总蛋白的76.70%,是主要的蛋白组分;其次是清蛋白,占总蛋白的11.80%;醇溶谷蛋白含量最少,仅为4.30%。氨基酸分析结果显示,12种早稻糙米中谷氨酸、天门冬氨酸、精氨酸和亮氨酸含量丰富,而胱氨酸、蛋氨酸、组氨酸和色氨酸含量较少。赖氨酸和苏氨酸分别是第1和第2限制性氨基酸。必需氨基酸与总氨基酸的比值均在55%以上。结论:与WHO模式相比,早稻糙米蛋白质具有较好的氨基酸组成,是一种优质蛋白质。     

A ventral approach to stereotaxy of the guinea pig brain

For skeletal muscles, a well-known match exists between the properties of motoneurones and those of their muscle fibres. Hence, the intramuscular distribution of different kinds of motoneuronal nerve endings (e.g. ‘slow’ versus ‘fast’) can be mapped by determining the distribution of the corresponding types of muscle fibre. As a background for further studies of motoneuronal plasticity, we needed precise measures of such distributions. Simple quantitative methods were developed for defining the position and extent of sub-populations of cells within a structure (e.g. the regional distribution of slow versus fast muscle fibres within a muscle cross-section): (a) The ‘mass vector method’ defined the relative position of the target cell cloud. A line was drawn between the calculated centre of mass for the target cells and that for the whole structure. The direction (a1) and length (a2) of this line gave a measure of the direction and degree of target cell eccentricity within the structure. (b) The ‘sector method’ delineated the region containing the target fibres. A circle around the centre of mass for the target fibres was subdivided into a number of equal sectors (standard setting: 20). The most remote point was found within each sector and a line joining these points defined the region of the target fibres. When applied to the ‘slow’ type I fibres of cross-sections from rat hindlimb muscles, the regional area estimates obtained by the sector method were highly correlated with, but 10% lower than those achieved by the well-established ‘convex hull’ method. Highly significant inter-muscular differences were observed for each one of the three new parameters described in this paper (a1, a2, b).     

黄酒对大鼠肠道微生物的影响

目的 观察黄酒对大鼠肠道微生物的影响,探讨其对肠道微生物调节作用的可能机制.方法 将30只SD大鼠随机分为对照组和给药组,对照组仅给予正常饲料喂食,给药组饲料中每日添加乙醇度为15.0％vol的黄酒5 ml,6周后处死大鼠,取肠道内容物做肠道乳杆菌属、大肠埃希菌及真菌等病原菌培养,利用统计方法研究两组的关系.结果 黄酒不影响大鼠的体重及血糖变化,两组差异无统计学意义；乳杆菌属给药组(351.1±13.6)×104 CFU/g、对照组(242.7±10.7)×104CFU/g,两组差异有统计学意义(P＜0.01),大肠埃希菌给药组(122.5±11.7)×105 CFU/g,对照组(137.3±20.2)×105CFU/g,两组差异有统计学意义(P＜0.05),真菌给药组(119.8±13.9)×102 CFU/g、对照组(134.2±18.3)×102 CFU/g,两组差异有统计学意义(P＜0.05).结论 适量饮用黄酒能增加肠道益生菌,减少肠道致病菌或条件致病菌,对肠道微生物有一定的调节作用.     

A rice chloroplast transit peptide sequence does not alter the cytoplasmic localization of sheep serotonin N‐acetyltransferase expressed in transgenic rice plants

Ectopic overexpression of melatonin biosynthetic genes of animal origin has been used to generate melatonin‐rich transgenic plants to examine the functional roles of melatonin in plants. However, the subcellular localization of these proteins expressed in the transgenic plants remains unknown. We studied the localization of sheep (Ovis aries) serotonin N‐acetyltransferase (OaSNAT) and a translational fusion of a rice SNAT transit peptide to OaSNAT (TS:OaSNAT) in plants. Laser confocal microscopy analysis revealed that both OaSNAT and TS:OaSNAT proteins were localized to the cytoplasm even with the addition of the transit sequence to OaSNAT. Transgenic rice plants overexpressing the TS:OaSNAT fusion transgene exhibited high SNAT enzyme activity relative to untransformed wild‐type plants, but lower activity than transgenic rice plants expressing the wild‐type OaSNAT gene. Melatonin levels in both types of transgenic rice plant corresponded well with SNAT enzyme activity levels. The TS:OaSNAT transgenic lines exhibited increased seminal root growth relative to wild‐type plants, but less than in the OaSNAT transgenic lines, confirming that melatonin promotes root growth. Seed‐specific OaSNAT expression under the control of a rice prolamin promoter did not confer high levels of melatonin production in transgenic rice seeds compared with seeds from transgenic plants expressing OaSNAT under the control of the constitutive maize ubiquitin promoter.     

Neuroprotective effects of dimerumic acid and deferricoprogen from Monascus purpureus NTU 568-fermented rice against 6-hydroxydopamine-induced oxidative stress and apoptosis in differentiated pheochromocytoma PC-12 cells

Context Oxidative stress plays a key role in neurodegenerative disorders, including Parkinson’s disease (PD). Rice fermented with Monascus purpureus Went (Monascaceae) NTU 568 (red mould rice) was found to contain antioxidants, including dimerumic acid (DMA) and deferricoprogen (DFC).

Objective The effects of DMA and DFC on 6-hydroxydopamine (6-OHDA)-induced cytotoxicity and potential protective mechanisms in differentiated PC-12 pheochromocytoma cells were investigated.

Materials and methods DMA (0–60?μM) or DFC (0–10?μM) was co-treated with 6-OHDA (200?μM, 24?h exposure) in differentiated PC-12 cells. Cell viability and intercellular reactive oxygen species (ROS) were measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) and 2′,7′-dichlorofluorescein-diacetate (DCFH-DA) assays, respectively. Cell apoptosis was determined by DNA fragmentation analysis and propidium iodide staining by flow cytometry. Western blot analysis was used to measure the levels of cell protein expression.

Results DMA and DFC significantly increased cell viability to 72% and 81% in 6-OHDA-induced differentiated PC-12 cell cultures, respectively. Furthermore, DMA and DFC reduced 6-OHDA-induced formation of extracellular and intercellular ROS by 25% and 20%, respectively, and decreased NADPH oxidase-2 expression in differentiated PC-12 cells. DMA and DFC inhibited 6-OHDA-induced apoptosis and decreased activation of caspase-3 via regulation of Bcl-2-associated X protein (Bax) and Bcl-2 protein expression in differentiated PC-12 cells.

Conclusion DMA and DFC may protect against 6-OHDA toxicity by inhibiting ROS formation and apoptosis. These results showed that the metabolites from M. purpureus NTU 568 fermentation were potential therapeutic agents for PD induced by oxidative damage and should be encouraged for further research.