A Structure–Function Study of a Catalytic Antiidiotypic Antibody to the Human Erythrocyte Acetyl Cholinesterase

The catalytic monoclonal antibody 9A8 (MA 9A8), antiidiotypic to the antibody AE-2 (MA AE2) produced to the active site of acetyl cholinesterase from human erythrocytes, was subjected to a structure–function study. The specific binding of MA 9A8 to MA AE2 (K 2.26 × 10⁹ M^–1) was found by the method of surface plasmon resonance, and the functional activity of MA 9A8 was demonstrated. Unlike acetyl cholinesterase, this antibody specifically reacted with the irreversible phosphonate inhibitors of esterases. A peptide map of MA 9A8 was analyzed by MALDI mass spectrometry. The Ser99 residue of its heavy chain was shown to be within the active site of the catalytic antibody. A computer modeling of the MA 9A8 active site suggested the existence of a catalytic dyad formed by Ser99 and His35. A comparison of the tertiary structures of the MA 9A8 and the 17E8 monoclonal antibody, which also exhibited the esterase activity and was produced to the stable analogue of the reaction transition state, indicated a practically complete coincidence of the structures of their presumed active sites.     

Involvement of pharyngeal muscles in compensatory responses of the respiration system to inspiration resistance load]

The present study was undertaken to test the hypothesis that recruitment of upper airway muscles in loaded breathing is a result of integration of peripheral chemoreceptor and pulmonary mechanoreceptor afferents. Experiments were performed in spontaneously breathing tracheostomized anesthetized rabbits. It had been studied the effects of inspiratory resistive loading to EMG activity of genioglossus muscle. In the intact rabbits the peak value and duration of inspiratory activity of genioglossus increased in loading. Imposition of resistive load in vagotomized animals did not evoke alteration in inspiratory activity of genioglossus in the first loaded breath. Hyperoxia decreased the response of genioglossus muscle to inspiratory loading and vagatomy. We conclude that hypoxic stimulation of peripheral chemoreceptors and decrease in volume-related afferent activity from pulmonary stretch receptors are major mechanisms of the upper airway muscle recruiment in inspiratory resistive loading.     

Behavior and Differentiation of the Neural Stem Cells in vivo

We studied the behavior and differentiation of human and rat neural stem cells after transplantation in the adult rat brain without immunosuppression. The rat stem cells were isolated from the presumptive neocortex of 15-day-old embryos. The human cells were isolated from the ventricular brain zone of 9-week-old embryos and cultivated for two weeks before transplantation. The results of histomorphological studies suggest that the microenvironment factors did not suppress the growth or development of transplanted stem cells. Both rat and human embryonic multipotent neural cells showed similar behavior and differentiation into neurons and glial cells. After transplantation, they continued to mitotically divide and migrated from the graft area to the surrounding tissue of a recipient brain. The presumptive glial cells migrated preferentially along the capillaries and fibrous structures of the recipient brain. Similar behavior of the rat and human neural stem cells in the microenvironment of the recipient adult rat brain and the absence of immune reaction suggest that the transplantation into the rat brain may serve as a model for studying the developmental biology of the human stem cells.     

A Comparative Assessment of Effects of Major Mediators of Acute Phase Response (IL-1, TNF-α, IL-6) on Breathing Pattern and Survival Rate in Rats with Acute Progressive Hypoxia

Journal of Evolutionary Biochemistry and Physiology - A pressing issue of the day is the identification of therapeutic targets to suppress the “cytokine storm” in COVID-19 complicated...     

Regioselective Synthesis,Structure, and Chemosensitizing Antitumor Activity of Cyclic Hydroxamic Acid Based on DL-Valine

Russian Journal of Bioorganic Chemistry - The reaction of DL-valine hydroxamic acid with triacetonamine proceeds as the N,N'-regioselective condensation to form...     

A new class of N-methyl-D-aspartic acid receptor agonists and antagonists--derivatives of imidazole-4,5- and pyrazole-3,4-dicarboxylic acids]

New agonists and antagonists of the N-methyl-D-aspartic acid (NMDA) receptors were found among the derivatives of 1- or 2-alkyl-substituted imidazole-4,5- and pyrazole-3,4-dicarboxylic acids. Lipophilic surrounding of the nitrogen atom in these compounds was found to determine their ability to be either agonists or antagonists, while the distance between the terminal acidic functions was the same. An increase in the lipophilicity can also cause loss of selective action upon the NMDA receptors and occurrence of non- NMDA antagonistic activity.     

Development of Biological Methods for Controlling the Aerobic Microorganism–Induced Corrosion of Carbon Steel

Cocultivation of destructor microorganisms and their antagonists decreases the corrosion loss of carbon steel by 20 to 80%. It was found that a microorganism can either accelerate or inhibit corrosion, depending on the nutrient. The magnitude of the effect on corrosion depends on the ability of the microorganism to respond to changes in the nutrient medium composition by releasing acidic or alkaline metabolites.