Contribution of the glycine site of NMDA receptors in rostral and intermediate-caudal parts of the striatum to the regulation of muscle tone in rats

The aim of the present study was to assess the contribution of the glycine site of NMDA receptors in the striatum to the regulation of muscle tone. Muscle tone was examined using a combined mechanoand electromyographic method, which measured simultaneously the muscle resistance (MMG) of the rat's hind foot to passive extension and flexion in the ankle joint and the electromyographic activity (EMG) of the antagonistic muscles of that joint: gastrocnemius and tibialis anterior. Muscle rigidity was induced by haloperidol (2.5 mg/kg i.p.). 5,7-dichlorokynurenic acid (5,7-DCKA), a selective glycine site antagonist, injected in doses of 2.5 and 4.5 microg/0.5 microl bilaterally, into the rostral region of the striatum, decreased both the haloperidol-induced muscle rigidity (MMG) and the enhanced electromyographic activity (EMG). 5,7-DCKA injected bilaterally in a dose of 4.5 microg/0.5 microl into the intermediate-caudal region of the striatum of rats not pretreated with haloperidol had no effect on the muscle tone. The present results suggest that blockade of the glycine site of NMDA receptors in the rostral part of the striatum may be mainly responsible for the antiparkinsonian action of this drug.     

Mist1: a novel basic helix-loop-helix transcription factor exhibits a developmentally regulated expression pattern

An equilibrium between positive and negative regulation of immunoreceptor signaling leads to the proper execution of lymphocyte activation. Tyrosine phosphorylation is the initial event in antigen receptor-induced lymphocyte activation. It is generally accepted that protein tyrosine kinases are involved in positive regulation, whereas protein tyrosine phosphatases are important for the negative regulation of tyrosine phosphorylation-dependent processes. However, the interaction between protein tyrosine kinases and protein tyrosine phosphatases is complex. This article discusses the role of two protein tyrosine phosphatases. CD45 and SHP-1, in the regulation of immunoreceptor signaling. SHP-1 acts as a negative regulator for several immunoreceptors, including those for T- and B-cell antigen receptors. The major role of CD45 is in the positive regulation of T- and B-cell antigen receptor signaling.     

Confluence operators and their relationships with revision,update and merging

In this paper we introduce confluence operators, that are inspired by the existing links between belief revision, update and merging operators. Roughly, update operators can be considered as pointwise revision, whereas revision operators can be considered as special case of merging operators. Confluence operators are to merging operators what update operators are to revision operators. Similarly, update operators can be considered as special case of confluence operators just as revision can be considered as special case of merging operators. Confluence operators gives all possible agreement situations from a set of belief bases.     

Structural, thermal expansion and heat capacity study of lead-free [(1 − x)(Na0.5Bi0.5)–xBa]Zr1−y Ti y O3 ceramics

Lead-free ceramics of Na_0.5Bi_0.5TiO₃–Ba(Ti,Zr)O₃ (NBT–BTZ) were prepared by solid phase hot pressing sintering process. The obtained samples show perovskite structure. Structural, the heat capacity, thermal expansion and pyroelectric measurements were made in wide temperature range. The broad anomalies of heat capacity and thermal expansion were observed, which approximately correspond to structural, pyroelectric and dielectric properties. It was concluded that these anomalies can be connected with temperature features of polar regions and with formation of long-range ferroelectric state. The obtained results are discussed in the framework of foreign ions/lattice imperfections, which create local electric and elastic fields. The NBT–BTZ system is expected to be a new promising candidate for lead-free electronic ceramics.     

Psychophysiological correlates of responsiveness in schizophrenia.

Measured responsiveness under stress through music preferences for 11 male and 9 female schizophrenics receiving no antipsychotic medication. These Ss were compared with a control group of 7 male and 13 female hospital staff or volunteers. Results indicate that higher schizophrenic responsiveness was related to lower skin conductance, fewer body movements, greater diastolic blood pressure decrease, better word recall, and shorter periods of institutionalization. Normal controls did not differ significantly in music preferences but were lower in all physiological measures. The finding that sweat gland activity, muscle tension, and diastolic blood pressure changes were related to stress in these acute schizophrenics paralleled the findings of A. F. Ax, et al (1969) with chronic schizophrenics. The interpretation that responsiveness is related to ability to cope with stress in schizophrenia is supported by results of the current study. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Processing and microstructural characterisation of laminated Ti-intermetallic composites synthesised using Ti and Cu foils

Ti-intermetallic laminated composites were fabricated by reaction synthesis in vacuum using Ti and Cu foils. The copper layers were completely consumed due to the formation of intermetallic phases. The Ti–Cu reaction was studied by interrupting in steps the reaction process to observe the microstructural changes. Microstructural examinations using scanning electron microscopy (SEM) and X-ray microprobe analysis demonstrated that five intermetallic compounds: Ti₂Cu, TiCu, Ti₃Cu₄, Ti₂Cu₃, TiCu₄ were formed after heat treatment at 1173 K for 1.8 ks. Heat treatment for 18 ks resulted in a microstructure consisting of Ti and TiCu layers, but with a thick Ti₂Cu interphase layer. The TiCu layers give high hardness to the composite, while unreacted titanium provides the necessary high ductility.