Habituation failure of skin conductance response after intraventricular administration of 6-hydroxydopamine in cats

Summary The effects of intraventricular administration of 6-hydroxydopamine on electrodermal activity were studied in cats. The treatment slowed down or eliminated habituation of the skin conductance response to repeated auditory stimuli. However, the impairment of habituation was not accompanied by an increase in the rate of spontaneous skin conductance fluctuation.     

Involvement of prolyl endopeptidase in ascidian fertilization

Summary Inhibitory effects on fertilization of the ascidian of three benzyloxycarbonyl(Z)-aminoacyl prolinals and Z-Gly-Pro-chloromethyl ketone added before and after insemination were examined. The results suggest that the prolyl endopeptidase is involved in the process of fertilization, especially in a process taking place between chorion elevation and cell cleavage.Acknowledgment. We are indebted to Dr T. Numakunai of the Marine Biological Station of Tohoku University for collecting the ascidians and to Dr M. Hoshi of the Tokyo Institute of Technology for his helpful discussion. We are also grateful to Dr T. Yoshimoto and Prof. D. Tsuru of Nagasaki University for their generous gift of Z-Gly-Prochloromethyl ketone. This work was supported by a Grant-in-Aid from the Ministry of Education, Science and Culture of Japan.     

Mutations affecting components of the SWI/SNF complex cause Coffin-Siris syndrome

By exome sequencing, we found de novo SMARCB1 mutations in two of five individuals with typical Coffin-Siris syndrome (CSS), a rare autosomal dominant anomaly syndrome. As SMARCB1 encodes a subunit of the SWItch/Sucrose NonFermenting (SWI/SNF) complex, we screened 15 other genes encoding subunits of this complex in 23 individuals with CSS. Twenty affected individuals (87%) each had a germline mutation in one of six SWI/SNF subunit genes, including SMARCB1, SMARCA4, SMARCA2, SMARCE1, ARID1A and ARID1B.     

Dissociation of digoxin-like immunoreactivity and Na+,K+-ATPase inhibitory activity in rat plasma

We measured endogenous digitalis-like factor (EDF) in rat plasma during acute saline infusion by two different procedures. Na+,K+-ATPase inhibitory activity in the rat plasma significantly increased during saline loading (7.8 +/- 2.2 vs 2.5 +/- 0.9%, with and without acute saline loading, respectively, p less than 0.05). On the other hand, the plasma digoxin-like immunoreactivity significantly decreased during acute saline loading (16.9 +/- 1.6 vs 32.0 +/- 2.8 pg digoxin equivalents/ml, with and without acute saline loading, respectively, p less than 0.01). These results indicate that the major substances detected by digoxin-like immunoreactivity and direct Na+,K+-ATPase inhibitory activity are completely different, at least in rat plasma.     

基于OpenGL的仿人机器人步行仿真研究

已有的仿真建模中,为了减少复杂性,大多将人足模型简化为点或圆弧,这与实际情况相差较远.在C++Builder 6.0环境下利用“Open GL”图形库建立了3D仿人型机器人双足步行仿真系统,用多关节串联机构模拟足部,实现包括由前脚掌支撑、足部转动的多种步态方式,并分析步行中各种步态间的转换,根据机器人脚跟、脚尖与地面接触状态的变化动态切换不同的步态方式,符合人足步行的实际情况,增强了机器人步行的灵活性与拟人性.该系统的控制部分采用位置反馈与正弦驱动相结合的行走控制方法,通过对人足模型的多关节动力学建模,有效地实现了机器人的稳定步行仿真,并实现了步行过程中的实时步态调整.     

Effect of win 18501-2 on the content of catecholamines and the number of catecholamine-containing granules in the rabbit hypothalamus

Zusammenfassung Der Hypothalamus von Kaninchen wurde nach Win 18501-2-Injektion biochemisch und elektronenmikroskopisch untersucht. Die Behandlung erzeugte auffallende Veränderungen im Noradrenalingehalt und in der Anzahl der Katecholamine enthaltenden granulierenden Vesiculae im Hypothalamus. Die Resultate scheinen zu zeigen, dass diese charakteristischen Vesiculae nur Noradrenalin enthalten und dass die Sedation des Kaninchens nach der Injektion von Win 18501-2 auf der Verminderung des Noradrenalins und der charakteristischen Vesiculae beruht.     

Effects of disodium EDTA on the cardiovascular responses to prostaglandin E1

Zusammenfassung Die Wirkung des Dinatrium-EDTA auf die Kreislaufreaktionen des Prostaglandin E₁ (PGE₁) wurde an narkotisierten Hunden untersucht. Das Ausmass der positiv chronotropen und inotropen Einflüsse des PGE₁ war während der Infusion von EDTA bedeutend geringer als das des PGE₁ vor der EDTA-Gabe. Die Gegenwart oder das Einströmen von Kalziumionen scheint in der pharmakologischen Wirkung des PGE₁ eine Rolle zu spielen.     

Molecular cloning and characterization of the rat NMDA receptor.

A complementary DNA encoding the rat NMDA receptor has been cloned and characterized. The single protein encoded by the cDNA forms a receptor-channel complex that has electrophysiological and pharmacological properties characteristic of the NMDA receptor. This protein has a significant sequence similarity to the AMPA/kainate receptors and contains four putative transmembrane segments following a large extracellular domain. The NMDA receptor messenger RNA is expressed in neuronal cells throughout the brain regions, particularly in the hippocampus, cerebral cortex and cerebellum.     

Chaperonin-mediated stabilization and ATP-triggered release of semiconductor nanoparticles

Various properties of semiconductor nanoparticles, including photoluminescence and catalytic activity, make these materials attractive for a range of applications. As nanoparticles readily coagulate and so lose their size-dependent properties, shape-persistent three-dimensional stabilizers that enfold nanoparticles have been exploited. However, such wrapping approaches also make the nanoparticles insensitive to external stimuli, and so may limit their application. The chaperonin proteins GroEL (from Escherichia coli) and T.th ('T.th cpn', from Thermus thermophilus HB8) encapsulate denatured proteins inside a cylindrical cavity; after refolding, the encapsulated proteins are released by the action of ATP inducing a conformational change of the cavity. Here we report that GroEL and T.th cpn can also enfold CdS semiconductor nanoparticles, giving them high thermal and chemical stability in aqueous media. Analogous to the biological function of the chaperonins, the nanoparticles can be readily released from the protein cavities by the action of ATP. We expect that integration of such biological mechanisms into materials science will open a door to conceptually new bioresponsive devices.     

Odorant receptor gene choice is reset by nuclear transfer from mouse olfactory sensory neurons

Of the approximately 1,000 odorant receptor (OR) genes in the mouse genome, an olfactory sensory neuron (OSN) is thought to express one gene, from one allele. This is reminiscent of immunoglobulin and T-cell receptor genes, which undergo DNA rearrangements in lymphocytes. Here, we test the hypothesis that OR gene choice is controlled by DNA rearrangements in OSNs. Using permanent genetic marking, we show that the choice by an OSN to express an allele of the OR gene M71 is irreversible. Using M71-expressing OSNs as donors for nuclear transfer, we generate blastocysts, embryonic stem (ntES) cell lines and clonal mice. DNA analysis of these cell lines, whose genome is clonally derived from an M71-expressing OSN, does not reveal DNA rearrangements or sequence alterations at the M71 locus. OSNs that differentiate from ntES cells after injection into blastocysts are not restricted to expression of M71 but can express other OR genes. Thus, M71 gene choice is irreversible but is reset upon nuclear transfer, and is not accompanied by genomic alterations.