TOCP染毒母鸡的神经电生理研究

对TOCP染毒母鸡进行为期7周的神经电生理监测,结果表明,TOCP主要影响远端周围神经,导致坐骨神经远端MCV和SCV减慢及腓肠肌EMG失神经样改变,而胫后神经H反射及重复电刺激无明显异常。     

振动对动物体内血脂水平的影响

为了研究振动对生物体内物质的耗散作用，本文在振动频率为２０Ｈｚ，振幅为０．１ｃｍ条件下对土母鸡的腹部脂肪作局部振动。并于振动一个疗程（２小时／天，５－７ｘ）的前后分别测试了血清中总胆固醇（ＴＣ）、甘油三脂（ＴＧ）和高密度脂蛋白胆固醇（ＨＤＬ－Ｃ）等各项指标。结果表明：上述特定频率、振幅与时间的振动使实验动物体内血清中总胆固醇、高密度脂蛋白胆固时与低密度脂蛋白胆固醇（ＬＤＬ－Ｃ）显著增加；甘油三酯显著减少（Ｐ＜０．０５）。ＴＣ的变化与ＨＤＬ－Ｃ、ＬＤＬ－Ｃ的变化呈正相关；ＴＧ的变化与ＨＤＬ－Ｃ的变化呈负相关。从而证实了特定参数的振动对动物体内的脂肪代谢有明显的作用，为人体施局部伍振动减肥的可行性提供了有益的参考。     

母鸡在排卵周期和抱窝血浆“黄体生成素类似物”和孕酮的浓度变化

本文用放射免疫分析法(RTA)测定了泰和母鸡在排卵周期和抱窝的不同生殖阶段,血浆“黄体生成素类似物”(“LH”)和孕酮(P)的浓度。结果表明:母鸡在排卵周期血浆“LH”和P的平均值分别为3.67±0.60ng/ml(x±SE)和459.50±30.87pg/ml,排卵前6～3h,血浆“LH”和P均出现浓度高峰,其峰值比相应的平均值高出1.1和1.3倍,差异非常显著(P<0.01)。抱窝鸡血浆“LH”和P在24h内的平均值分别为2.27±0.22ng/ml和319.46±12.15pg/ml,显著地低于母鸡在排卵周期的平均值(P<0.05),且在24h内的不同时间,未见有浓度高峰出现。     

人血清反应因子基因的原核表达及鸡卵黄多克隆抗体的制备

目的 在原核系统中表达人血清反应因子(serum response factor,SRF)基因,制备鸡卵黄抗SRF抗体并鉴定其特性.方法 构建SRF表达载体PGEX-T-2-SRF,并在大肠杆菌中以异丙基-β-D-硫代半乳糖苷(isopropy-β-D-thiogalactoside,IPTG)诱导表达.表达产物经谷胱甘肽-S转移酶(glutathione-S-transferase,GST)亲和层析柱纯化后,用十二烷基硫酸钠聚丙烯酰胺凝胶电泳(sodium dodecyl sulphate polyacrylamide gel electrophoresis,SDS-PAGE)进行鉴定.用纯化的SRF免疫海蓝白母鸡,制备鸡抗SRF抗体.抗体的效价及特异性用蛋白质印迹技术进行测定和分析,免疫荧光鉴定其在心肌细胞中的定位.结果 构建的重组质粒PGEX-4T-2-SRF在大肠杆菌中得到高表达,诱导表达的蛋白存在于包涵体和细菌裂解上清液中,纯化的SRF经SDS-PAGE鉴定呈单一条带.以纯化的SRF免疫制备了鸡抗SRF抗体.蛋白质印迹技术结果表明,该抗体可与原核表达的SRF特异性结合,抗体效价为1:5000.免疫荧光证实该抗体可以和心肌细胞的细胞核特异性结合.结论 在原核细胞中表达了SRF制备的鸡抗SRF的抗体对SRF能进行特异性结合.     

VALIDITY AND USE OF A NON-PARALLEL INSULIN ASSAY FOR PHARMACOKINETIC STUDIES OF THE RAPID-ACTING INSULIN ANALOGUE,INSULIN ASPART

A radioimmunoassay (RIA) for insulin was validated for reliable measurement of the human insulin analogue, insulin aspart, by correction of non-linear measurements. Specificity was equivalent for several species of insulin, except insulin aspart. A non-linear hyperbolic model fitted insulin aspart with a correction formula for non-linearity of: z = 1503y/(1398 - y), where y denotes measured concentration and z denotes true concentration.

Matrix-effects were insignificant for human, porcine, and canine heparin-plasma and for human and porcine serum. The coefficient of variation was below 15% for 80–800 pmol/L human and porcine insulin and for 80–600 pmol/L insulin aspart. The limit of detection for insulin aspart was 11.5 pmol/L with a lower limit of quantification of 17.5 pmol/L. Dilution of serum with Pharmacia dilution media introduced no significant error. In conclusion, this paper demonstrates that a non-parallel radioimmunoassay can be used to estimate accurate concentrations of insulin aspart.     

Yo jyo hen shi ko, a novel Chinese herbal, prevents nonalcoholic steatohepatitis in ob/ob mice fed a high fat or methionine-choline-deficient diet.

BACKGROUND: Oxidative stress plays a role in the pathogenesis of nonalcoholic steatohepatitis (NASH). Yo jyo hen shi ko (YHK) is a complex compound purported to reduce reactive oxygen species (ROS) by blocking the propagation of radical-induced reactions. The aim of this study was to evaluate the role of the effect of YHK in experimental NASH. METHODS: NASH was induced in male ob/ob mice by a high-fat (HF) diet or methionine/choline-deficient (MCD) diet for 4 weeks. YHK-treated animals received YHK solution orally (20 mg/kg/day) in both experimental diets (n=6; each group) while control animals received only vehicle. RESULTS: The MCD and HF groups developed moderate diffuse macrosteatosis, hepatocellular ballooning, and a diffuse inflammatory infiltrate. With the addition of YHK, there was a marked reduction in macrosteatosis in both groups. This was associated with decreased lipoperoxide and reduced glutathione-GSH concentrations as well as reduced serum aminotransferases and improved histological markers of inflammation. These changes were also associated with weight loss in the MCD+YHK group and diminished weight gain in the HF+YHK group. CONCLUSION: YHK therapy blunts the development of macrosteatosis in these models of NASH and significantly reduces markers of oxidative stress. YHK also diminishes weight gain in this obesity prone model. Our findings warrant further study on the mechanisms involved with these effects.     

Tau proteins-enhanced Ca/calmodulin (CaM)-dependent phosphorylation by the brain supernatant of diisopropyl phosphorofluoridate (DFP)-treated hen: tau mutants indicate phosphorylation of more amino acids in tau by CaM kinase II

Diisopropyl phosphorofluoridate (DFP) produces organophosphorus ester-induced delayed neurotoxicity (OPIDN) in hen, human, and other sensitive species. A single dose of DFP (1.7 mg/kg, s.c.) produces mild ataxia in 7–14 days in hens, followed by progression to severe ataxia or paralysis. We studied the effect of DFP administration on Ca²⁺/calmodulin-dependent phosphorylation of tau proteins by the brain supernatants of control and DFP-treated hens. Brain supernatants from DFP-treated hens showed enhanced in vitro phosphorylation of htau40 and its various mutants, but no change in the two-dimensional phosphopeptide pattern, when compared to control hen brain supernatants. Analysis of tau mutants phosphorylated by brain supernatant and recombinant CaM kinase II α-subunit showed that (1) brain supernatant CaM kinase II is mainly responsible for the phosphorylation of Ser⁴¹⁶, (2) Ser³⁵⁶, but probably not Ser²⁶², is phosphorylated by CaM kinase II, (3) no amino acid between Lys³⁹⁵–Ala⁴³⁷ except Ser⁴¹⁶ is phosphorylated by CaM kinase II, (4) a number of amino acids in the tau molecule, which are phosphorylated by the brain supernatant in the absence of Ca²⁺/calmodulin are also mildly phosphorylated by CaM kinase II. The enhanced Ca²⁺/calmodulin-dependent phosphorylation of tau proteins by brain supernatant of DFP-treated hens that includes phosphorylation of a number of amino acids is likely to alter the functional properties of tau proteins in OPIDN. The hyperphosphorylated tau may destabilize microtubules, alter axonal transport, and result in degeneration of axons in OPIDN.     

The vestibular nuclei in the domestic hen

Summary Stereotaxic injections of small quantities of horseradish peroxidase (HRP) are made in the vestibular complex in the hen and the labelled cells due to retrograde transport of the tracer enzyme are studied, especially in the vestibular complex but also in other parts of the brain stem. The superior vestibular nucleus sends commissural fibres to the superior, medial, and descending nuclei and to Deiters' complex. The cell group A projects to the contralateral superior nucleus and to the Deiters' complex. The medial nucleus projects to the contralateral superior and descending nuclei, Deiters' complex, as well as strongly to the medial nucleus. The descending nucleus projects commissurally to the superior nucleus, the medial nucleus and the Deiters' complex, as well as heavily to the descending nucleus. The nucleus Deiters ventralis, the nucleus Deiters dorsalis, the cell group B and the tangential nucleus do not project to any other vestibular nuclei. Furthermore, the medial nucleus projects to the superior and descending nuclei and the Deiters' complex on the same side. The descending nucleus projects to the superior and medial nuclei on the same side. Finally, the superior nucleus, the medial nucleus, the descending nucleus, and the Deiters' complex receive fibres from the ipsilateral nucleus of Darkschewitsch and the nucleus ectomammillaris, as well as bilaterally from the pontine but mainly from the bulbar reticular formation.     

Identification of potential components of the transport mechanism for Na+ in the hen colon and coprodaeum

The binding of³H-benzamil to homogenates of epithelium removed from the colon and coprodaeum of hens was studied. A low capacity high affinity binding component was detected. The binding constants for benzamil and amiloride to this component were similar to those obtained when these ligands were used to inhibit transport in intact epithelia. The mean potency ratio of benzamil to amiloride was 12.8 measured by binding compared with 11.6 from functional inhibition. Binding activity was present in tissues taken from animals fed on low sodium diets and those containing a normal sodium content. In the presence of sodium the affinity of benzamil was slightly reduced, but only in tissues taken from animals on a low salt diet. Only a small fraction of the total binding activity was present in the apical surface of low salt tissues indicating that in homogenates a small percentage of the total activity is associated with functional sodium entry sites. It is suggested that the major part of the binding activity detected in homogenates represents components of the sodium ion translocation mechanism which are en route for the apical membrane.