晕可宁颗粒对急、慢性梅尼埃病模型的影响

目的　探讨晕可宁颗粒的主要药效学 ,为临床提供药效学资料及治疗学基础。方法　采用三氯甲烷破坏豚鼠一侧膜迷路感受器模型 ,探讨受试药对眼震颤、摆头及旋转的影响 ;采用内淋巴囊和内淋巴管阻塞手术复制豚鼠膜迷路实验性膜迷路积水模型 ,研究内耳组织平均中阶面积 (SMA)增加率及形态学的变化。结果　抑眩宁阳性对照组、晕可宁颗粒 (8、16g/kg)模型给药组豚鼠眼球震颤次数减少 ,差异有显著意义 (P <0 .0 5 )。成功复制了不同程度膜迷路积水豚鼠模型 ,表现为前庭膜重度膨出 ,前庭阶缩小 ,膜蜗管增大 ,SMA增加率变大 ,差异有显著意义 (P <0 .0 1) ;晕可宁颗粒灌胃后可减轻豚鼠实验性膜迷路积水的程度 ,差异有显著意义 (P <0 .0 1) ;但与空白对照组比较SMA增加率差异无显著意义 (P >0 .0 5 )。结论　晕可宁颗粒可以减轻内淋巴囊积水程度 ,对梅尼埃病症状有对抗治疗作用。     

Genetics of reovirus: the relationship of interference to complementation and reassortment of temperature-sensitive mutants at nonpermissive temperature.

Temperature-sensitive mutants of reovirus type 3 are capable of interfering with the replication of wild-type reovirus type 3. The interfering activity correlated with the ability of pairs of mutants to complement at 39°: Pairs of noninterfering mutants (tsD × tsE) yielded efficient complementation (indexes of 10–50); pairs of interfering mutants (including members of groups ts A, B, G) did not produce significant complementation (indexes ～ 1). The ability of pairs of mutants to reassort at 39° generally followed a similar pattern. Thus interference is an important property of ts mutants of reovirus and needs to be considered when genetic interactions are being studied at 39°.     

Identification and characterization of fast-sedimenting SV40 nucleoprotein complexes.

Simian virus 40 (SV40) nucleoprotein complexes were extracted from nuclei of infected monkey cells and fractionated on neutral sucrose density gradients. Four forms of SV40 chromatin were distinguished by their labeling kinetics and apparent sedimentation coefficients: Replicating viral DNA in 95 S SV40 chromatin was converted to 75 S chromatin when viral DNA replication was completed. A portion of the 75 S chromatin was rapidly assembled into 200 S nucleoprotein complexes and subsequently into 240 S complexes. The 75 S and the fast-sedimenting complexes were further characterized and compared with mature SV40 virus by equilibrium density centrifugation, plaque assay, and electron microscopy. These experiments suggest that the fast-sedimenting forms may represent virion precursors or a subclass of salt-labile virions, but they contain little or no mature virus.     

Parallel investigations of the effects of adenosine on evoked potentials and cyclic AMP accumulation in hippocampus slices of the rat.

In slices of rat hippocampus, adenosine and its receptor agonist, 2-chloro-adenosine, were both found to (a) enhance the intracellular accumulation of cyclic adenosine monophosphate (cAMP) and (b) depress neuronal evoked responses to electrical stimulation. The differences in the dose/effect curves for the biochemical and electrophysiological changes cast doubt on a causal relationship between the two effects.     

The mechanism of stimulation of the antiviral factor (AVF) in Nicotiana leaves. The involvement of phosphorylation and the role of the N-gene.

Crude preparations of a precursor of the antiviral factor (pre-AVF) were made from noninfected Nicotiana leaves, either carrying the N-gene or from which the N-gene is absent. These pre-AVF preparations could be activated to give antiviral activity. Crude enzyme preparations, made only from N-gene-carrying plants, but regardless of TMV-infection, served as activating systems. This activation requires ATP, CAMP and cGMP and is associated with the appearance of a new phosphor ylated material seen by polyactylamide gel electrophoresis. The induced antiviral activity has been purified as AVF but was separated from the phosphorylated material. It is proposed that an activating system, determined by the N-gene, is itself being activated through phosphorylation following TMV infection and processes a “pre-AVF” to make active AVE.     

Inhibition of vaccinia virus late protein synthesis by isatin-beta-thiosemicarbazone: characterization and in vitro translation of viral mRNA.

Thespecific effect of istin-βthiosemicarbozone (IBT) was manifested after vaccinia virus late protein synthesis had commenced. At 6 hr after infection, viral protein synthesis was inhibited by about 9596. We confirmed that λ portion of the virus-specific RNA appears to be degraded (B. Woodson and W. K. Joklik, 1965, Proc. Nat. Acad. Sci. USA 54,946–953). Nevertheless, the amount of viral RNA that was capped, properly methylated, and polyadenylylated, was reduced by only about 50%. Moreover, RNA from IBT-treated cells stimulated cell-free protein synthesis to one-half the level obtained with RNA from control cells. Polyacrylamide gel electrophoretic analysis further demonstrated that RNA from IBT-treated cells was translated into late viral proteins in vitro. Thus, it seems possible that the inhibition of protein synthesis in IBT-treated cells does not result entirely or directly from either an inhibition of mRNA synthesis or from λ depletion of mRNA caused by accelerated degradation. An alternative possibility, that accelerated degradation is secondary to λ more immediate effect of the drug on protein synthesis, was considered.     

Asparate and/or glutamate may be transmitters in hippocampal efferents to septum and hypothalamus

The high affinity uptakes of asparate (Asp) and glutamate (Glu) were heavily and selectively reduced in the lateral septum (?67%) and mammillary body (?52%) by surgical interruption of their connections with the hippocampal formation in rats. There was no reduction in the medial septum. GABA uptake, glutamate decarboxylase, choline acetyltransferase and carnitine acetyltransferase were not reduced. Choline acetyltransferase was increased (+51%) in the lateral septum. The normal activities of these parameters showed characteristic distribution patterns between medial and lateral septum, mammillary body and hippocampus. The ratio of Glu and Asp uptakes was not changed by lesions and vaired only little between the regions sampled.     

Topographical representation in rabbit cerebellar flocculus for various afferent inputs from the brainstem investigated by means of retrograde axonal transport of horseradish peroxidase.

A small amount of horseradish peroxidase (HRP) was injected into several small areas of the flocculus and adjacent ventral paraflocculus of albino rabbits. Labeled cells were surveyed through the inferior olive, vestibular nuclear complex, nucleus reticularis tegmenti pontis, pontine nucleus and abducens nucleus. Distribution of labeled neurons in these structures varied depending on the location of injection sites, indicating the existence of a fine topographical organization for afferent inputs in the flocculus and adjacent ventral paraflocculus.