Structure and origin of axonal terminals innervating neurons of the vestibular ganglia

Structural organization of the frog axonal terminals, realizing the synaptic contact with neurons of the vestibular ganglion have been studied electron microscopically. Two kinds of axonal terminals are revealed. They differ in quantitative and qualitative composition of their synaptic vesicles convergated simultaneously in various combinations to the ganglious neurons. Using the axonal retrograde transport of horseradish peroxidase, the nature of these axonal terminals is analysed. Their source is demonstrated to be neurons of the reticular formation and ventral vestibular nucleus of the medulla oblongata, as well as Purkinje's cells of the cerebellum.     

Assessment of "impulsive" behavior by the method with time calculation

In this paper the problem of "impulsive" and "self-control" behaviour in animals and the experimental models for their assessment are discussed. It is pointed out that a widely accepted model for assessment of impulsive behaviour in animals predominantly measures their ongoing properties of impulsivity/self-control independently on belonging them to the certain types of higher nervous activity. In contrary, our model at the first instance assesses the typological characteristics of animals, including impulsivity and self-control, by their abilities to perform or not to perform an appropriate behaviour. The differences in the data obtained by these two different models and the possible reasons for it are discussed.     

Organization of interneuronal relationships in the nucleus accumbens during impulsive and self-control behavior in cats

Under conditions of a choice between a high-valuable delayed and a low-valuable immediate food rewards, cats were divided into 3 groups on the basis of their individual strategy of behavior: (1) choosing predominantly the high-valuable reward because of inhibition of the instrumental response (capable of self-control), (2) choosing predominantly the immediate low-valuable reward (impulsive), and (3) with a mixed pattern of reactions (ambivalent). Coherent activity of nucleus accumbens neurons which was a characteristic of interactions between nearby cells was assessed by the method of crosscorrelation. It was found that the total number of interneuronal interactions in cats capable of self-control exceeded that displayed by impulsive cats. In those rare cases when impulsive cats performed long-latency responses not typical of them, the number of interneuronal interactions was the same as during the self-control behavior. In animals of different groups, the number of interneuronal interactions was higher during erroneous responses as compared to correctly performed reactions. The results suggest an important role of systemic activity of neurons in the nucleus accumbens in the organization of the long-latency reaction pattern, characteristic of self-control behavior.     

Cooperative neuronal activity of the n. accumbens and the frontal cortex in cats trained to choose stimuli of various value

It was shown that the two-way interaction between neurons of the frontal cortex and n. accumbens progressively increases, whereas their regularity simultaneously decreases with the rise in impulsiveness and drop in self-control in behavior. In case of the long-latency instrumental reactions, a control of the frontal cortex neurons by neurons of the n. accumbens weakens during presentation of conditioned stimuli only in "impulsive" animals, which is correlated with low network activity of the n. accumbens. Comparison of patterns of fronto-accumbal interactions during performance of the same type of activity revealed similar correlations in the neuronal pairs before and during presentation of conditioned stimuli, whereas different patterns corresponded to different types of activity.     

AmylPepPred: Amyloidogenic Peptide Prediction tool

We present an efficient computational architecture designed using supervised machine learning model to predict amyloid fibril forming protein segments, named AmylPepPred. The proposed prediction model is based on bio-physio-chemical properties of primary sequences and auto-correlation function of their amino acid indices. AmylPepPred provides a user friendly web interface for the researchers to easily observe the fibril forming and non-fibril forming hexmers in a given protein sequence. We expect that this stratagem will be highly encouraging in discovering fibril forming regions in proteins thereby benefit in finding therapeutic agents that specifically aim these sequences for the inhibition and cure of amyloid illnesses.

Availability

AmylPepPred is available freely for academic use at www.zoommicro.in/amylpeppred