Endocrine-dependent expression of circadian clock genes in insects

Current models state that insect peripheral oscillators are directly responsive to light, while mammalian peripheral clock genes are coordinated by a master clock in the brain via intermediate factors, possibly hormonal. We show that the expression levels of two circadian clock genes, period (per) and Par Domain Protein 1 (Pdp1) in the peripheral tissue of an insect model species, the linden bug Pyrrhocoris apterus, are inversely affected by contrasting photoperiods. The effect of photoperiod on per and Pdp1 mRNA levels was found to be mediated by the corpus allatum, an endocrine gland producing juvenile hormone. Our results provide the first experimental evidence for the effect of an endocrine gland on circadian clock gene expression in insects. Received 31 October 2007; received after revision 7 January 2008; accepted 9 January 2008 D. Dolezel, L. Zdechovanova: These authors contributed equally to this work.     

Cichlid familial intrarelationships and the placement of the neotropical genus Cichla (Perciformes,Labroidei)

The current status of our understanding of cichlid intrafamilial relationships is investigated and novel data are presented resolving a basal trichotomy of the African and Neotropical radiations (Oliver, 1985). The claim that the African Cichlidae is non-monophyletic is supported and the little known Zairean genus Heterochromis is identified as the sistergroup of all other African and Neotropical Cichlidae combined. Throughout the study emphasis has been placed upon the resolution of the precise phylogenetic relationships of the enigmatic Neotropical genus, Cichla; a taxon whose placement has been thought critical for successful intra-familial analyses. Analysis of the evidence currently available argues strongly in favour of a close phylogenetic relationship between Cichla and the sisterpair, Crenicichla and Teleocichla. Given this phylogenetic scheme one of the most interesting aspects to arise is the striking morphological parallels between Cichla and many of its distantly related percoid relatives.     

乙基紫分光光度法测定牛血清白蛋白

研究了乙基紫 (EV)与牛血清白蛋白 (BSA)的结合反应 .在pH =7.2的条件下 ,BSA的加入使乙基紫的最大吸收峰波长红移 5nm(5 95→ 6 0 0nm) ,并使染料吸光度增大 .6 0 0nm处吸光度与BSA在一定浓度范围内有线性关系 ,线性响应范围为 1.0 0× 10 -7～ 2 .0 0× 10 -6mol/L ,检测下限为 8.0 0× 10 -8mol/L .该法简便、快速、干扰少、灵敏度较高 ,用于牛血清白蛋白样品测定结果满意 .初步探讨了EV -BSA结合机理 ,Scatchard图表明有两类结合 ,第一类结合的最大结合数为 2 .3,结合常数为 6 .5× 10 5L/mol;第二类结合的最大结合数为 5 .6 ,结合常数为 2 .0× 10 5L/mol.讨论了乙醇、十六烷基三甲基溴化铵 (CTAB) ,十二烷基苯磺酸钠 (DBS)对结合反应的影响     

Comparison of the time courses of luteinizing hormone (LH) secretion rates during continuous stimulation by LH-releasing hormone (LH-RH) in vivo and in vitro

Summary The patterns of LH secretion during constant stimulation of the pituitary glands of estradiol-treated ovariectomized rats with a maximally stimulating amount of LH-RH in vivo and in vitro correspond with each other qualitatively and quantitatively. In vitro the changes with time of the LH secretion rate are somewhat retarded, especially the occurrence of desensitization.     

Evidence for no relationship of the pineal activity with the neonatal shrinkage of Leydig cells in the rat

Summary The collective volume of Leydig cells in prenatally pinealectomized newborn rats declined as sharply as in intact newborn rats. Also, the collective volume in pups born in the dark declined in a fashion similar to that in pups born in the light. The results indicate that neither the pineal gland nor the light is responsible for the neonatal shrinkage of Leydig cells.This study was supported in part by a Grant-in Aid for Scientific Research (No. 548067) from the Ministry of Education, Science and Culture of Japan.     

The effect of shock on blood oxidation-reduction potential

Oxidation-reduction (redox) potential measurements were made in the blood of rabbits subjected to hemorrhagic shock followed by treatment with a mild oxidizing agent (albumin). Control redox potential reading corrected for pH was –8.8±1.3 millivolts (mV) in arterial blood (A) and –18.0±2.0 mV in venous blood (V). This A-V difference indicated that hydrogen equivalents coming from muscle and other tissues were partially consumed in the lungs. A 20-mV drop on the V and a 13 mV on the A side was seen after shock. This did not fully return to control 2 h after return of the shed blood. Infusion of 2 g of albumin/kg/h raised the V redox potential to control, but it returned to untreated levels when the albumin was discontinued. The reductive load imposed on the animal by shock appeared to be large and not readily reversed by reperfusion or by the quantity of albumin given. Thus, it may be concluded that cellular respiration had not been adequately restored. This reductive load may impede recovery by suppression of cellular respiration and other cell and organ functions.     

黄鼬甲状腺的形态位置及组织结构研究

本试验应用解剖学,常规组织学及银染技术,对8例野生成体黄鼬(4(?)4(?))的甲状腺进行观测.结果表明,黄鼬甲状腺左右各一叶,呈细长条状,紧贴气管两侧近腹侧面,于第6～18气管软骨环之间,两叶之间未见连接部.腺体内结缔组织间隔发达,腺实质周边滤泡大,中间滤泡小.泡腔内均填充大量红色胶体.C细胞具嗜银性,单个嵌于滤泡上皮细胞之间,少数散布于滤泡间结缔组织内.本研究结果不仅填补了黄鼬甲状腺形态位置及组织结构方面资料的空白,而且揭示了其形态及位置的特殊性,与其他哺乳类均有不同.由此为研究该物种的生物学特性提供必要的形态学资料,同时亦为解剖学增添了新的内容.     

CD44v6、E-cadherin和ki-67蛋白质与腮腺多形性腺瘤的生物学行为相关性研究

为检测腮腺多形性腺瘤中CD44v6、E-cadherin和ki-67蛋白表达,以探讨其与腮腺多形性腺瘤生物学行为的相关性。应用免疫组织化学SP法染色检测腮腺多形性腺瘤组、多形性腺瘤恶变组和瘤旁非瘤组织组各组间CD44v6、Ecadherin和ki-67蛋白表达。结果显示,(1)CD44v6、E-cadherin和ki-67在腮腺多形性腺瘤组中的阳性表达率分别为100%、96%和73.8%;(2)E-cadherin和ki-67在腮腺多形性腺瘤组、多形性腺瘤恶变组和瘤周非瘤组织间的阳性表达率均有差异,其表达与腮腺多形性腺瘤的浸润转移有关;(3)CD44v6在腮腺多形性腺瘤组与瘤周非瘤组织组,多形性腺瘤恶变组与瘤周非瘤组织组中的表达有统计学差异。由此可知,E-cadherin和ki-67与腮腺多形性腺瘤的生物学行为有关,可作为新的肿瘤标志物,其表达对判断预后有一定的价值。     

用C18-RPLC柱及UV检测器分离和测定蜥蜴松果体中的褪黑激素

研究了褪黑激素和消炎痛在反相Ｃ１８柱上的色谱行为,流动相为甲醇－磷酸盐缓冲溶液体系,主要考察了ｐＨ值及洗脱液的组成对色谱保留的影响,对蜥蜴松果体中的褪黑色激素进行了完全分离和定量测定。     

重金属Hg^2＋对NBS修饰前后血清蛋白圆二色谱的影响

为了探明重金属Hg^2＋进入体内，对血清蛋白固有结构和功能的影响，我们用Hg^2＋对NBS修饰前后血清蛋白HSA和BSA进行处理，然后分析血清蛋白的圆二色谱特性，结果表明，近紫外区未修饰的HSA和BSA均具有典型的α螺旋构象；Hg^2＋处理或NBS修饰BSA溶液，均引起α-螺旋含量减少和三级结构构象的改变．Hg^2＋处理HSA，α-螺旋含量略有增加，构象也有变化．而NBS修饰导致α簇结构的严重破坏，蛋白构象无序化程度加深．修饰对BSA、HSA光谱特性的影响不同，可能与这两种蛋白的结构差异有关．