基于拟脑智能系统的烤烟烟叶分级研究

对烟叶进行检测与分级是控制烟叶质量的重要手段之一.研究烟叶质量的合理表征参数及其自动提取方法,以及烟叶辅助分级系统,是迫切需要解决的问题.应用人工智能方法和计算机技术进行烤烟烟叶自动分级,提出一种借鉴生物脑信息处理结构的烤烟烟叶智能分级系统.该系统由思维模型、感觉模型和行为模型3个子系统构成,分别模拟分级专家的思维智能、感知智能和行为智能,具有学习与记忆、判断与模糊推理、分级决策等多种思维功能,以及图像自动采集、上下位机通信等协调与控制功能.应用该系统进行烟叶分级试验的结果与分级专家分级结果的平均一致率可达到85%,与人工分级水平相当.     

脑络通胶囊对大鼠局灶性脑缺血模型的影响

目的观察脑络通胶囊对大鼠大脑中动脉缺血模型的影响。方法通过线栓法建立大鼠大脑中动脉(MCA)局灶性脑缺血模型,动物经给药3次,观察脑络通胶囊对脑缺血大鼠的行为状态、脑缺血面积、脑组织形态学的作用。结果脑络通胶囊1.72、0.86、0.43g/kg剂量均能明显改善大鼠脑缺血后的行为状态,缩小缺血范围,降低缺血程度,使病变的脑组织得到明显地改善。     

生长抑素对大鼠乳腺斯钙素基因表达的影响

将泌乳期大鼠分为对照组、CS组和SS组,利用RT-PCR法对大鼠乳腺组织斯钙素基因进行检测,分析生长抑素对大鼠乳腺斯钙素基因表达的影响。结果表明:乳腺中有STC1表达,无STC2表达。生长抑素对泌乳期大鼠乳腺斯钙素基因表达起下调作用,半胱胺作用相反。以上结果提示生长抑素和半胱胺可能参与乳腺钙代谢的调节,且通过STC1发挥作用。     

三种有机磷农药胚胎期暴露对新生鼠脑组织结构的影响

探讨了3种常用的有机磷农药胚胎期暴露对新生鼠脑组织结构的影响。在母鼠妊娠期7.5～11.5 d时,连续5 d每天分别经皮下注射2 mg/kg bw的二嗪磷(diazinon)、2 mg/kg bw的毒死蜱(chlorpyrifos)及50 mg/kg bw乙酰甲胺磷(acephate),显微镜下观察并计数大脑皮层S1区胶质细胞和神经元数量及比率,以及海马CA1、CA3区锥体细胞的数量及体积密度。结果表明,二嗪磷与毒死蜱处理分别使得大脑皮层S1区胶质细胞数减少了14.29%和21.43%;毒死蜱处理导致胶质细胞与神经元比率下降了24.19%;二嗪磷与毒死蜱处理后海马CA1区锥体细胞数量分别下降了9.30％与20.93％,毒死蜱处理后锥体细胞体积密度下降了27.05％;二嗪磷与毒死蜱处理后海马CA3区锥体细胞数量分别下降了22.22％和19.44％,锥体细胞体积密度分别下降了23.54％和18.98％;而乙酰甲胺磷对新生鼠大脑皮层与海马细胞均无明显影响。     

The effects of Saw palmetto on flumethrin-induced lipid peroxidation in rats

In the present study, 40 male Wistar albino rats were used and divided into 4 groups. The first group served as the control group; the second group was administered Saw palmetto extract at the dose of 20 mg/kg/bw; the third group was administered flumethrin at the dose of 15 mg/kg/bw; and the fourth group was administered a combination of 20 mg/kg/bw Saw palmetto extract and 15 mg/kg/bw flumethrin, for 21 days, orally. After the trial period, blood and tissue (liver, kidney and brain) samples were taken from the rats. Saw palmetto extract did not cause significant alterations in plasma and tissue malondialdehyde (MDA) levels, serum and tissue nitric oxide (NO) levels, erythrocyte and tissue superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px) activities when compared to the controls (p > 0.05). Flumethrin led to increased plasma and tissue MDA levels, serum and tissue NO levels, tissue GSH-Px activities and decreased erythrocyte and tissue SOD and CAT activities, and erythrocyte GSH-Px activity, compared to the controls (p < 0.05). The flumethrin and Saw palmetto extract combination increased erythrocyte SOD activity and decreased brain GSH-Px activity as compared to flumethrin (p < 0.05). In conclusion, it was determined that Saw palmetto extract did not cause any negative effect on the prooxidant-antioxidant balance. While flumethrin stimulated lipid peroxidation; Saw palmetto extract at the dose of 20 mg/kg/bw did not exhibit enough antioxidant effect in rats.     

Enolase在鸭疫里默氏杆菌侵袭鸭脑微血管内皮细胞中的作用

旨在明确鸭疫里默氏杆菌烯醇化酶(Enolase)在其侵袭鸭脑微血管内皮细胞(DBMEC)以及血脑屏障(BBB)中的作用。本研究以鸭疫里默氏杆菌RA-LZ01株为亲本株,利用同源重组和结合转移的方法构建enolase基因缺失株ΔEnolase和回复株cΔEnolase,并测定RA-LZ01、ΔEnolase和cΔEnolase对DBMEC黏附和侵袭能力的差异;用上述菌株感染雏鸭,测定雏鸭血液和脑组织中的载菌量。结果表明,与亲本株RA-LZ01相比,缺失株ΔEnolase对DBMEC的黏附率和入侵率均极显著降低;回复株cΔEnolase恢复了对DBMEC的黏附和入侵能力。感染RA-LZ01、ΔEnolase和cΔEnolase菌株的雏鸭的血液载菌量无显著差异;与感染RA-LZ01和cΔEnolase菌株的雏鸭相比,感染ΔEnolase菌株的雏鸭脑组织中的载菌量极显著降低。以上结果说明,Enolase与鸭疫里默氏杆菌黏附和入侵DBMEC以及入侵雏鸭脑组织显著相关,可能为介导鸭疫里默氏杆菌突破鸭血脑屏障的毒力因子。     

AsKC11, a Kunitz Peptide from Anemonia sulcata,Is a Novel Activator of G Protein-Coupled Inward-Rectifier Potassium Channels

(1) Background: G protein-coupled inward-rectifier potassium (GIRK) channels, especially neuronal GIRK1/2 channels, have been the focus of intense research interest for developing drugs against brain diseases. In this context, venom peptides that selectively activate GIRK channels can be seen as a new source for drug development. Here, we report on the identification and electrophysiological characterization of a novel activator of GIRK1/2 channels, AsKC11, found in the venom of the sea anemone Anemonia sulcata. (2) Methods: AsKC11 was purified from the sea anemone venom by reverse-phase chromatography and the sequence was identified by mass spectrometry. Using the two-electrode voltage-clamp technique, the activity of AsKC11 on GIRK1/2 channels was studied and its selectivity for other potassium channels was investigated. (3) Results: AsKC11, a Kunitz peptide found in the venom of A. sulcata, is the first peptide shown to directly activate neuronal GIRK1/2 channels independent from Gi/o protein activity, without affecting the inward-rectifier potassium channel (IRK1) and with only a minor effect on K_V1.6 channels. Thus, AsKC11 is a novel activator of GIRK channels resulting in larger K⁺ currents because of an increased chord conductance. (4) Conclusions: These discoveries provide new insights into a novel class of GIRK activators.     

Distribution and induction of cytochrome P450 1A1 in the rainbow trout brain

Cytochrome P450 (CYP) 1A1 participates in the activation as well as detoxification of environmental pollutants such as aromatic hydrocarbons. This CYP form is also efficiently induced by aromatic hydrocarbons. The presence of CYP 1A1 in the brain might thus be of physiological and toxicological importance. In the present investigation on rainbow trout, the distribution of 7-ethoxyresorufin-O-deethylase (EROD) activity, a cytochrome CYP 1A1 catalyzed reaction, was measured in whole tissue homogenates from brain parts. In control fish, a relatively high activity was found in the rainbow trout olfactory bulb compared to the other brain parts. Although an EROD induction (3 to 7-fold) by β-naphthoflavone (BNF) was recorded in all brain parts from the rainbow trout, the highest induced activity was measured in the olfactory bulbs. To ascertain the distribution of EROD activity in cells, whole brain tissue was subfractionated by differential centrifugation. The fractionation scheme separated mitochondria (P2 fraction) and microsomes (P3 fraction) as determined by marker enzymes and electron microscopy. In control rainbow trout, a low EROD activity could be measured in the P2 fraction. BNF induced the EROD activity in both P2 and P3 fractions. Western blotting showed the induction by BNF of a protein band in the P2 and P3 fractions with a molecular mass around 58,000 when highly specific anti-cod CYP 1A1 antibodies were used. ELISA measurements confirmed the induction of CYP 1A1 protein in the rainbow trout brain subcellular fractions.     

神经型一氧化氮合酶在大菱鲆脑组织中的分布及定位

[目的]探明神经型一氧化氮合酶(nNOS)在大菱鲆(Scophthalmus maximus)脑组织中的分布情况,为揭示大菱鲆脑组织中一氧化氮(N0)的生理功能提供形态学资料.[方法]分别采用NADPH-d组织化学染色法和免疫组织化学法对大菱鲆脑组织中的nNOS进行定位研究.[结果]NADPH-d组织化学染色结果显示,大菱鲆大脑皮质中有蓝色的神经元和神经纤维存在.神经元呈梭形、锥形等形状,神经纤维呈串珠状且无序交织;小脑中NOS阳性神经元在分子层分布稀疏,在颗粒层分布密集,浦肯野细胞胞核淡染.经免疫组织化学法染色后,可观察到大脑皮质中nNOS免疫组化反应阳性物质呈深棕色;小脑皮质的分子层、颗粒层及浦肯野细胞层均有nNOS阳性神经元分布,浦肯野细胞呈免疫组织化学阳性反应.[结论]大菱鲆脑组织中的NOS类型主要限于nNOS,且nNOS在神经活动中发挥重要作用,也进一步证实N0在不同物种中具有一些共同的作用,但不同物种或相同物种不同组织中NO分布及含量存在差异.