Vol 20, No 4 (2020)

Neutrophilic granulocytes are one of the key cellular factors of innate immunity. The review presents data on the morphology, migration and utilization of neutrophilic granulocytes, phagocytosis and degranulation processes, neutrophilic extracellular traps, plasticity of neutrophils, their role in systemic inflammatory reactions and regulation of adaptive immunity.

Objective. We aimed to analyze the effect of an agonist of vasopressin type 2 receptors, 1-desamino-8-D-arginine-vasopressin, DDAVP, on the content of the brain neurotrophic factor, BDNF, in the hippocampus and blood plasma of rats exposed to vital stress.

Material and methods. The study carried out on female Wistar rats divided into 4 groups: first group included control animals, 2 — those who received DDAVP intranasally in small doses (once 2 ∙ 10^–9 g, course 20 ∙ 10^–9 g), 3 — those who exposed to the stress of a threat to life caused by the experience of the death of a partner from the actions of a tiger python, 4 — those who exposed to stress and received DDAVP. BDNF concentration in samples was measured by immunohistochemical method.

Results. An increase in the content of BDNF in blood plasma in rats exposed to acute psychogenic stress and received DDAVP therapy was revealed on the tenth day after stress. There was no effect of stress, DDAVP, or their combined effect on the BDNF content in the homogenate of hippocampal tissues.

Conclusion. The results of this pilot study indicate that DDAVP has a modulatory effect on BDNF metabolism in rats exposed to vital stress. It is assumed that an increase in the level of neurotrophin in the blood of rats reflects the activation of compensatory processes.

M.E. Lobashev and V.В. Savvateev in 1959 obtained unique data on the expansion of the adaptive capabilities of the organism when training the properties of higher nervous activity by the formation of conditioned food reflexes to stimuli that exhaust the nervous system. Apparently, the formation of a conditioned connection help to overcoming stressful effects, adaptation to restrictive conditions, and changes in the functioning of the nervous system. To test this assumption, the influence of stressful influences hypoxia on learning and memory of Drosophila in the paradigm of conditioned reflex suppression of courtship was studied. The results were obtained on the enhancement of the ability to learn under hypoxic exposure. These experimental conditions did not affect memory formation. The effect of hypoxia on chromosomes through the formation of double-stranded breaks was revealed. The data are discussed in light of the relationship between neuroplasticity processes and mechanisms of adaptation to stressors.

The relevance of this work is determined by the high prevalence and social significance of cerebrovascular diseases and the need to develop effective methods for verifying neuronal damage due to cerebral ischemia in experimental models.

The aim of this study was to assess the possibility of immunohistochemical revealing of neurofilaments to detect axonal injury in cerebral ischemia models.

Materials and methods. A model of transient focal cerebral ischemia by the left middle cerebral artery occlusion was reproduced in male Wistar, SHR and WKY rats. Axonal injury was assessed by immunohistochemical reactions for neurofilament proteins using SMI-32 and 2F11 antibodies.

Results. In cerebral ischemia, damage to nerve fibers occurs, manifested by thickening of axons, their varicose expansion and segmental accumulation of neurofilament proteins. These changes are more noticeable with an immunohistochemical reaction to the SMI-32 marker of neurofilament heavy chain.

Conclusions. The use of antibodies to the non-phosphorylated neurofilament heavy chain makes it easy to identify degenerating nerve fibers and can be recommended as an alternative method for detecting axonal injury.

Objective: to develop algorithm of prediction of troponin I elevation 3^d day postoperatively depending on troponin I level on 1^st after on-pump coronary artery bypass grafting using SAS Enterprise Guide 6.1 software.

Materials and methods

Data collection was performed according to prospective non-randomized clinical trial AMIRI — CABG in Pavlov First St. Petersburg State Medical University, Saint Petersburg, Russia between 2016-2019 years with 336 patients with indications to coronary artery bypass grafting.

Algorithm was developed for on-pump group (n=128). There is database which include following information: troponin I level 1^st and 3^в days postoperatively. There was determined distribution of variables and linear regression was used for predicting model construction and its precision was estimated as well.

Results. There was developed algorithm of prediction of myocardial damage after on-pump coronary artery bypass grafting with linear regression model using SAS Enterprise Guide 6.1 software.

Conclusion. Presented algorithm of linear regression allows to compare independent groups for nominal data.

The relevance. Meropenem is a broad-spectrum carbapenem antibiotic widely used to treat patients with sepsis / septic shock. Critically ill patients are usually supported with one of the forms extracorporeal blood purification. However, data on the effect of various extracorporeal support techniques on the pharmacokinetics and pharmacodynamics of meropenem are insufficient or contradictory.

Aim: To evaluate the effectiveness of meropenem dosage regimens in the treatment of septic patients during extracorporeal blood purification.

Materials and methods. Plasma concentrations of meropenem were monitored in three critically ill patients with sepsis or septic shock. Patients were treated using various extracorporeal support techniques. Meropenem was used as empirical antibacterial mono- or complex therapy (1 g every 8 or 12 hours). Meropenem concentrations in plasma were determined by validated assay methods on Acquity ultraefficient liquid chromatography (UPLC) H-Class system.

Results. It is shown that the meropenem plasma concentration in critically ill patients changes significantly. It was found that the standard meropenem dosing regimens in patients with sepsis / septic shock during continuous hemodiafiltration do not ensure the achievement of the PK/PD target of 100% T>MIC for sensitive strains (MIC≤2 mg/L) and for intermediate resistance pathogens (2≤MIC<8 mg/L). Continuous hemofiltration and selective adsorption of lipopolysaccharide have a less pronounced effect on the clearance of meropenem.

Conclusion. To increase the effectiveness of antibacterial therapy, it is necessary to conduct research aimed at developing protocols for dosing antibacterial drugs for the treatment of sepsis during extracorporeal blood purification.