Bulletin of Experimental Biology and Medicine最新文献

The formation of functional connections between cells derived from neuronal progenitor cells (NPCs) and the developed neuronal network is a crucial task in neurobiology and cellular technologies for medical applications. We developed a technique to co-culture NPCs and mature neuronal cells in a three-chamber microfluidic chip in vitro and studied the features of functional connections among cells derived from NPCs during their integration into a network of differentiated neurons. Starting from day 20 of primary culture development, a network forms from integrated NPCs, which ensures the distribution of bioelectrical activity among neurons in a manner similar to that of differentiated cells.

In rats subjected to increasing restriction of motor activity starting from day 21 days of life, copper content was evaluated by electron paramagnetic resonance (EPR) spectroscopy by analyzing the levels of copper-containing paramagnetic complexes in the heart and liver tissues. Copper content was assessed by the intensity of the characteristic EPR signal from the Cu²⁺-diethyldithiocarbamate complex (Cu²⁺-(DETC)₂). It was found that after restriction of motor activity for 30 days, copper content in the heart and liver tissues increased by 2.2 and 2.9 times, respectively.

An increase in the ploidy of cardiomyocytes (CMCs) determines the potential for their hypertrophic growth. We analyzed the changes in CMC ploidy and size of the interventricular septum in patients with hypertrophic cardiomyopathy (HCM) and tetralogy of Fallot (TF). The ploidy of CMCs in children and adult patients with HCM and children with TF was 1.5-2-fold higher than in individuals without cardiovascular pathology, and it did not change with age. The size of the CMCs was also larger by 1.3-2 times in patients with HCM and TF, compared to the control groups. However, the increase in CMCs size was more significant in HCM than in TF. The proportion of multinucleated CMCs was significantly lower in patients with HCM compared to controls and was by almost 2 times higher in patients with TF. Thus, myocardial hypertrophy in HCM is mainly due to the polyploidy of mononucleated CMCs, whereas in TF, the proportion of multinucleated CMCs increases.

Monoclonal antibodies (mAbs) of the IgG1 isotype obtained to the full-length recombinant pneumolysin (rPly) did not recognize or poorly recognized conformational epitopes of native pneumolysin in ELISA. At the same time, polyclonal antibodies (pAbs(rPly)) detected native pneumolysin in sandwich ELISA when they were used as capture and detecting antibodies simultaneously. All mAbs(rPly) inhibited erythrocyte hemolysis induced by native pneumolysin. The combined use of mAbs(rPly) did not reveal an increase in optical density in ELISA and an increase in inhibition hemolytic activity, which suggests that mAbs(rPly) are directed to the same or spatially closely located epitopes. pAbs(rPly) more effectively inhibited erythrocyte hemolysis than mAbs(rPly).

The redox status of aminothiols in the blood plasma of 15 patients with end-stage renal disease before and against the background of hemodialysis therapy was compared with that of relatively healthy volunteers. An increase in the plasma content of total cysteine and homocysteine in patients before dialysis was revealed. An increase in the level of oxidized forms of these compounds was also noted. The hemodialysis procedure was accompanied by a significant shift of the redox status towards an increase in the reduced forms typical of healthy people. Oxidized forms of aminothiols can be used as biomarkers of uremic conditions in patients with end-stage renal disease. At the same time, the predominance of reduced forms of compounds may be an indicator of the effectiveness of renal replacement therapy, including hemodialysis.

Stress-induced cardiac injury (SICI) was modeled on female Wistar rats using a 24-h immobilization. SICI was quantified by ^99mTc-pyrophosphate accumulation in the myocardium. Blockade of β₁- and β₂-adrenergic receptors (AR) led to a decrease in SICI. β₁-AR antagonists nebivolol and atenolol almost completely prevented SICI. The selective β₂-AR antagonist ICI 118,551 increased SICI, while the selective β₃-AR antagonist L-748337 did not affect heart damage. The selective β₂-AR agonist formoterol increased cardiac tolerance to stress. These findings suggest that β₁-AR play a key role in the pathogenesis of SICI. Stimulation of β₂-AR enhances cardiac tolerance to stress. β₃-AR are not involved in the pathogenesis of SICI.

We studied the effect of α₂-adrenoreceptor stimulation after preliminary I_f blockade on the function of the Langendorff-isolated rat heart in the acute stage of experimental myocardial infarction. Stimulation of α₂-adrenoreceptors with clonidine (10^-6 M) against the background of I_f blockade with ZD7288 (10^-9 M) reduced the contractility of the left ventricular myocardium, HR, coronary blood flow, and the duration of the left ventricular myocardium contraction in sham-operated rats and animals with acute myocardial infarction. The duration of relaxation and contraction cycle during α₂-adrenoreceptor stimulation after preliminary I_f blockade (10^-9 M) was increased in sham-operated rats and in animals with acute myocardial infarction. Stimulation of adrenoreceptors against the background of application of ZD7288 in a concentration of 10^-5 M decreased the left ventricular pressure, HR, coronary blood flow, and the duration of left ventricular myocardial contraction in both groups. The duration of the relaxation and contraction cycle during α₂-adrenoreceptor stimulation against the background of I_f blockade (10^-5 M) increased in sham-operated rats and animals with acute myocardial infarction.

The structural MRI of the cortex, subcortical structures, hippocampal subfields, and brainstem regions in patients with persecutory delusions in schizophrenia (ICD-10 code: F20) and delusional disorder (ICD-10 code: F22.0) were analyzed. Patients demonstrated multiple regions of decreased cortical gray matter thickness, reduced volumes of the left thalamus and some hippocampal sub-fields compared to mentally healthy subjects. No alterations in brainstem structures were found. The results were analyzed within the framework of the transnosological model of delusions.

We have previously demonstrated multidirectional changes in trypsin activity and some serum biochemical parameters in rats under conditions of water and food deprivation with following satiation. In the present study, administration of soybean trypsin inhibitor (STI) to animals subjected to water and food deprivation caused a moderate decrease in trypsin activity and an increase in the serum concentration of total protein, which attested to deceleration of protein metabolism. Significant changes in the content of cholesterol and triglycerides against the background of STI administration were also found indicating intensification of lipid and energy metabolism. These findings suggest that STI prevents disturbances of metabolic processes in the body under conditions of water and food deprivation. However, the peculiarities of STI influence on metabolic processes require further study.

We studied the effect of a krypton-oxygen mixture on the key signaling pathways associated with ischemic tolerance and suppression of secondary damage in a model of photoinduced stroke in male Wistar rats. In animals breathing the krypton-oxygen mixture, the expression of the transcription factor NF-κB (p50) in the brain was suppressed, indicating anti-inflammatory shifts in the brain tissue upon exposure to krypton, in parallel, increased content of phosphorylated forms of glycogen synthase kinase 3β (GSK-3β) and protein kinase B (Akt), components of the preconditioning cascade, was revealed. These results indicate a high potential of krypton in reducing acute cerebral disorders.