Changes in the size and shape of the synaptic vesicles in the sensorimotor cortex of the rat brain in the initial phases of kindling

The sensorimotor area of rat cerebral cortex was subjected to repeated electrical stimulation at 10-min intervals, with resultant formation and progressive lengthening of self-sustained after-discharges (SSAD). One and 60 min after the third SSAD ended, we carried out an electron microscopy morphometric analysis of the agranular synaptic vesicles in type I synapses (after Gray) in the second cortical layer of the homotopic area of the unstimulated hemisphere. One minute after the seizure ended, 5.8% enlargement of the synaptic vesicles compared with the control was demonstrated in zone II of the synapse (0.1-0.2 micron from the active zone of the synapse). Neither the size nor the shape of the synaptic vesicles in the other parts of the synaptic apparatus altered. Sixty min after the seizure ended, a 5.5% enlargement of the synaptic vesicles in zone I (0.0-0.1 micron) and a 5.4% enlargement of those in zone II was found. The synaptic vesicles in zone I in the experimental animals were more oval than in the controls. Our findings support the vesicular theory and testify that hyperfunction, up to temporary exhaustion of the synaptic apparatuses, produces a change in the transmitter content of the synaptic vesicles. A raised amount of transmitter in the synaptic vesicles near the active zone could be one of the factors responsible for continued hyperexcitability of the tissue one hour after the seizure had ended. The results likewise support the concept of two mechanisms of synaptic vesicle formation, and hence of the existence of two different vesicle populations.     

Neutrophil-stimulating activity of staphylococci based on reactive chemiluminescence data

The neutrophil-stimulating properties of 38 S. aureus strains and 32 S. epidermidis strains were studied in the reaction of luminol-mediated chemiluminescence. All S. aureus strains and 29 S. epidermidis strains were found to possess neutrophil-stimulating activity, the mean activity index for S. aureus being significantly higher. The stimulating activity of the strains varied within a wide range (the variation coefficient was 120.0 +/- 21.9%) and did not correlate with the content of protein A in bacterial cells and the degree of their hydrophoby. The opsonization of staphylococci with normal human serum enhanced the neutrophil reaction 1.5- to 100-fold and simultaneously leveled out the chemiluminescence indices in experiments with different strains (the variation coefficient was 8.0 +/- 1.5%). The nature of the neutrophil-stimulating effect of staphylococci and its relationship to the exploratory reactions of phagocytes are discussed.     

Automated Food-Procuring Movement-Related Neuronal Activity in the Basolateral Amygdala of the Rat

We studied the impulse activity of neurons of the basal and lateral amygdalar nuclei generated when experimental animals (rats) performed fast stereotyped food-procuring movements by the forelimb. Within the basolateral amygdala, there are neurons whose activity is related to different stages of getting off the food, and according to the characteristics of their spiking these neurons should be divided into a number of subpopulations. Activation forestalling the movement initiation by 0.5-1.0 sec was observed in most neurons of the basolateral amygdala; this is considered a manifestation of excitation related to a motivation component of the food-procuring behavior. Activation of amygdalar neurons following movement initiation can result from generation in this structure of additional excitation necessary for successful performance of a complete food-procuring motor cycle.     

Expression of a lipocalin in prokaryote and eukaryote cells: quantification and structural characterization of recombinant bovine beta-lactoglobulin.

In this paper we quantify and characterize the expression of recombinant beta-lactoglobulin (rBLG) in prokaryote and eukaryote cells. In Escherichia coli we used the pET26 vector, which permits the secretion of rBLG in periplasm. We studied the expression of rBLG in COS-7 cells and in vivo in mouse tibialis muscle. The expression of rBLG was measured by two immunoassays specific, respectively, for BLG in its native and denatured conformation. We observed that rBLG was essentially expressed in a denatured form in E. coli even in the periplasm, whereas rBLG in eukaryote cells was found in its native conformation.     

A process optimization for bio-catalytic production of substituted catechols (3-nitrocatechol and 3-methylcatechol

Background  

Substituted catechols are important precursors for large-scale synthesis of pharmaceuticals and other industrial products. Most of the reported chemical synthesis methods are expensive and insufficient at industrial level. However, biological processes for production of substituted catechols could be highly selective and suitable for industrial purposes.