EFFECT OF SOME IMMUNOMODULATORY DRUGS ON EMBRYONIC DEVELOPMENT OF DANIO RERIO FISH.

At the current stage of healthcare development, the inclusion of immunomodulators in the complex pharmacotherapy of various immunoinflammatory and viral diseases is widely discussed, but due to the lack of sufficient research and a broad evidence base, not all drugs with similar properties are used in medicine. According to the information obtained from the instructions for the use of immunomodulators, it was obtained that the main contraindications to their use include the prescription of children, pregnant women, and women during breastfeeding. In this study, we evaluated the effects of immunomodulatory drugs: aminodihydrophthalazindione sodium and meglumine acridonacetate, on the early developmental stages of Danio rerio (Zebrafish) embryos.

Synthesis of New Amidoethanesulfonamides of Betulonic Acid.

New potentially biologically active amidoethanesulfonamides of betulonic acid were synthesized by the acid chloride method via conjugation of betulonic acid with 2-aminoethanesulfonamides as the free bases.

Synthesis of 2-Aminoethanesulfonamides of Betulinic and Betulonic Acids.

New potentially biologically active sulfonamide derivatives of pentacyclic lupane-type triterpenoids, the sulfonamide group of which was bonded to C-17 of the triterpene skeleton through an amidoethane spacer, were synthesized via conjugation of 2-aminoethanesulfonamides to betulinic and betulonic acids in the presence of Mukaiyama reagent (2-bromo-1-methylpyridinium iodide).

[The effectiveness of botulinum therapy of trigeminal neuralgia]. / Effektivnost' botulinoterapii pri trigeminal'noi nevralgii.

OBJECTIVE: To evaluate the treatment protocol with the use of onabotulinum toxin type A (botox) and the efficacy of a single botulinum therapy procedure for clinical manifestations in patients with trigeminal neuralgia (TN). MATERIAL AND METHODS: We studied 90 patients (57 women, 33 men), including 80 people with primary TN and 10 people with secondary TN. Then 20 patients with primary TN (11 women and 9 men, mean age 61.8 years) received local injections of onabotulinum toxin type A (botox). Clinical examination included taking anamnesis, assessment of pain on a visual analogue scale (VAS), assessment of the frequency of pain paroxysms, taking into account the average indicator (0 to 100 seizures during the day); neurosensory examination according to the developed protocol with the definition of pain, temperature, tactile sensitivity, the study of stimulus-dependent pain; MRI of the brain to diagnose neurovascular conflict. RESULTS: A month after the injections, the pain intensity practically did not change (8.5 versus 7.2 points on the VAS), but the number of paroxysms decreased (31.2 versus 22.5 seizures per day). Two months after the use of botox, the number of pain attacks continued to decrease (31.2 versus 17.7; Mann-Whitney U-test, p=0.006). At the same time, there was a decrease in pain intensity according to the VAS (8.5 versus 6.1, t-test 2.75 points; p=0.02). After three months, there was a decrease in the number of paroxysms from 31.2 to 9.2 (paired Student's test, p<0.001) and the severity of pain (8.85 versus 4.0 points on the VAS, paired t-test 3.95 points, p<0.001). There were significant differences in the average dose of carbamazepine (867.5 versus 670.8 after 3 months, t-test 196.7 mg, p=0.02). In TN patients who underwent destructive operations with exposure to the peripheral branches of the trigeminal nerve, signs of severe neurosensory deficit on the face and burning pain are added to the main symptoms, which corresponds to the clinical criteria of post-traumatic trigeminal neuropathy. CONCLUSION: Local injections of type A onabotulinum toxin (botox) are minimally invasive, safe and effective symptomatic therapy for patients with TN. Persistent sensory disturbances that develop in patients after destructive surgeries call into question the safety of these therapies for TN.

Recovery of Impaired Memory: Expression of c-Fos and Egr-1 Transcription Factors during Restoration of Damaged Engram in the Chick Brain.

Impairment of protein synthesis in the brain during learning prevents memory consolidation and results in amnesia, which until recently has been regarded irreversible. However, in some cases impaired memory could be restored by various "reminder" stimuli. The present study is based on the hypothesis that even in behaviorally profound amnesia, some disintegrated fragments of the engram are preserved in the brain and could be re-integrated into the whole system by specific types of stimuli. The aim of the present study was to test this hypothesis in an experimental model of pharmacologically induced memory impairment in young chicks and to reveal the brain areas involved in this process by mapping of reminder-induced expression of transcriptional factors c-Fos and Egr-1. We show that reminder treatment results in the recovery of memory impaired by protein synthesis inhibition during learning and induces c-Fos and Egr-1 expression in the brain regions involved in learning in this behavioral model. The patterns of c-Fos and Egr-1 induced expression in animals with impaired memory differed from the patterns of animals with unimpaired memory and as well as naïve animals with no memory. Thus, analysis of activity-induced c-Fos and Egr-1 expression revealed the brain regions that were specifically activated by the reminder treatment. At the behavioral level, this treatment led to memory recovery. Altogether, these results suggest that the reminder-induced transcriptional activity in the brain of amnestic animals occurs in regions maintaining the engram fragments that reintegrate to recover the impaired memory.

Prenatal Sensory Stimulation Induces BDNF Gene Expression in the Brain and Potentiates the Development of Species-Specific Predisposition in Newborn Chicks.

We studied the effects of light and non-specific sound stimulation of domestic chick embryos on their filial preference as well as on the expression of two transcriptional factors c-Fos and Egr-1 and neurotrophin BDNF in the embryo brain. Prenatal light stimulation increased preference of the "natural" object, thus producing a priming effect. In the brain of E19 embryos, c-Fos and Egr-1 were expressed at a high basal level and neither light nor sound stimulation affected the number of cells expressing these factors. BDNF mRNA was also present in a number of brain areas of non-stimulated embryos, but light and sound stimulation enhanced the expression of BDNF mRNA in brain structures associated with filial imprinting. These findings suggest that BDNF is probably involved in the effects of prenatal priming on the development of species-specific behavior.

Paradoxical Effect of NMDA Receptor Blockade in Chicks on Learning and Memory in Passive Avoidance Model.

Activity of NMDA receptors is a prerequisite for numerous but not all forms of neuronal plasticity and learning. The present study examined the role of NMDA receptors in standard, weak, and repeated passive avoidance training in young chicks. Injection of MK-801, an antagonist of NMDA receptor, prior to strong training episode impaired subsequent memory recall. Moreover, repeated training did not restore the lost memory. In the double weak training protocol, the impairing effect of MK-801 was observed only when it was injected prior to the second but not to the first training episode. These results suggest that activation of NMDA receptors is not a necessary stage for memory acquisition in the weak training task. In contrast, the mechanisms of strong training depending on activation of NMDA receptors can be probably involved into the second training episode performed against the background of existing NMDA receptor-independent memory about the first training episode.

Pro-Cognitive Effects of Non-Peptide Analogues of Soluble Amyloid Peptide Precursor Fragment sAPP.

We studied pro-cognitive effect of two heterocyclic low-molecular-weight compounds that serve as non-peptide analogues of soluble fragment of amyloid peptide precursor (sAPP). Intracerebroventricular and systemic administration of peptide mimetics P2 and P5 improved weak memory on the model of passive avoidance in chicks and in the object location task in mice. Both compounds were effective if administered close to the moment of training or 4 h after it. The time windows and dose range for the pro-cognitive effects of the mimetics were similar to those observed in previous studies with sAPP peptide fragments.

[CHARACTERISTIC OF ANTIBIOTIC-ASSOCIATED DIARRHEA IN PATIENTS WITH ACUTE CEREBRAL CIRCULATION DISORDER].

This full-design study included patients admitted to the Regional Vascular Centre in 2013 and was aimed to obtain more detailed information on the need for medical aid, indications for antibacterial therapy and the spectrum of the drugs being prescribed 42 patients presented with antibiotic-associated diarrhea caused by Clostridium difficile. The composition of antibiotics used for mono- and combined therapy was analysed, details of the clinical picture are described, the importance of timely diagnostics and adequate treatment is emphasized.

Brain morphology imaging by 3D microscopy and fluorescent Nissl staining.

Modern optical methods (multiphoton and light-sheet fluorescent microscopy) allow 3D imaging of large specimens of the brain with cell resolution. It is therefore essential to refer the resultant 3D pictures of expression of transgene, protein, and other markers in the brain to the corresponding structures in the atlas. This implies counterstaining of specimens with morphological dyes. However, there are no methods for contrasting large samples of the brain without their preliminary slicing. We have developed a method for fluorescent Nissl staining of whole brain samples. 3D reconstructions of specimens of the hippocampus, olfactory bulbs, and cortex were created. The method can be used for morphological control and evaluation of the effects of various factors on the brain using 3D microscopy technique.

Glutamate receptor modulator dimebon stimulates consolidation and reconsolidation of weak memory in chicks.

Effects of glutamate receptor modulator dimebon on memory consolidation and reconsolidation were investigated in passive avoidance paradigm in newborn chicks. Systemic administration of 0.1 mg/kg dimebon 5 min before or 4 h after "weak" training resulted in formation of long-term memory. Dimebon administration in combination with memory reactivation 24 h after "weak" training recovered the memory decayed by the time of reminder and ensured its subsequent long-term maintenance over 24 h. Thus, we showed the possibility for dimebon-induced recovery of the memory that decayed and had no manifestations in behavior. Dimebon administration potentiated early and late stages of memory consolidation in learning as well as in memory reconsolidation following its reactivation.

Selective impairments to memory consolidation in chicks produced by 5'-iodo-2'-deoxyuridine.

The aim of the present work was to study the role of DNA synthesis in the formation of different types of memory in neonatal chicks. The nucleotide analogs 5'-iodo-2'-deoxyuridine (IdU) and 5'-bromo-2'-deoxyuridine (BrdU) were used; these are incorporated into DNA, impairing its function, and have amnestic actions in defined models of learning in mice. We studied the effects of 5'-iodo-2'-deoxyuridine of the formation of long-term memory in chicks during training in different models: passive avoidance, imprinting, taste aversion, and spatial learning in a maze. In the taste aversion model, i.p. administration of IdU (10 mg/kg 5 min before or 50 min after training) had an amnestic effect on testing 1-2 days after training. IdU-induced amnesia developed more than 6 h after training, while administration of IdU 2 h after training had no amnestic effect. 5'-Bromo-2'-deoxyuridine also had a similar amnestic action in the taste aversion model. In the passive avoidance, imprinting, and spatial maze learning models, administration of IdU at the same dose before and after training did not induce amnesia. These data lead to the suggestion that DNA synthesis in the brain may play a critical role in the mechanisms of memory consolidation in chicks in types of learning such as taste aversion.

Effects of an imprinting procedure on cell proliferation in the chick brain.

We report here studies on the effects of an imprinting procedure on cell proliferation in neonatal chicks in brain structures known to undergo plastic changes in imprinting. Proliferating cells were detected immunohistochemically on brain sections by incorporation of pre-training doses of 5-bromodeoxyuridine (BrdU) into DNA; numbers of new cells were counted in the intermediate medial mesopallium, the intermediate arcopallium, the medial part of the mesopallium and the nidopallium, the dorsocaudal nidopallium, the hippocampus, and the parahippocampal region 24 h and seven days after training. The intermediate medial mesopallium showed an increase in the number of BrdU-positive cells 24 h after training. However, at seven days post-training, the number of BrdU-containing cells decreased in the medial nidopallium and mesopallium, in the dorsocaudal nidopallium, and the right intermediate medial mesopallium. Thus, the imprinting procedure had differently directed transient and long-term influences on the genesis of new cells in the chick brain, inducing the appearance of a large number of cells in the parenchyma of the brain one day after training and decreases in the numbers of cells at later time points. This double effect may be associated with the fact that the imprinting procedure simultaneously initiates two brain processes involving the control of cell proliferation - one related to maturation of a species-specific functional system for tracking individuals of the same species and one related to remembering the characteristics of the actual parent.

[Selective disruption of memory consolidation in chicks produced by 5'-iodo-2'-deoxyuridine].

We tested the hypothesis that DNA synthesis is involved in molecular mechanisms of memory consolidation. Nucleotide analogs 5'-iodo- and 5'-bromo-2'-deoxyuridine impair DNA functions being incorporated into elongated DNA chain and cause amnesia in a number of training models in mice. We studied possible amnestic effects of 5'-iodo-2'-deoxyuridine (IdU) in different training models in newborn chicks--in passive avoidance, taste aversion, imprinting and spatial learning in a maze. In the taste aversion model injection of IdU (10 mg/kg 5 min before or 50 min after training) produced amnesia at test 1-2 days after training, at the same time it had no effect on memory retention in test 6 h after training. IdU injection 2 h after training produced no amnesia. Similar amnestic effect in taste aversion model was found for 5'-bromo-2'-deoxyuridine (BrdU). In models of imprinting, passive avoidance and spatial learning IdU injection before or after training had no effect on memory retention. These data presuppose that brain DNA synthesis might play a critical role in mechanisms of memory consolidation in taste aversion learning in chicks.

[Effect of filial imprinting procedure on cell proliferation in the chick brain].

In the present study we tested the hypothesis that memory formation during visual imprinting might be related to generation of new cells in the brain of newborn domestic chicks. Cell proliferation was examined in the intermediate medial mesopallium (IMM), arcopallium intermedium (AI), medial part of nidopallium and mesopallium (MNM), nidopallium dorso-caudalis (Ndc), hippocampus (Hp) and area parahippocampalis (APH), as well as in corresponding ventricular zones. Number of new cells was measured by BrdU incorporation 24 h or 7 days after training, BrdU was injected before training. 24 h after imprinting the number of BrdU-positive cells increased significantly in IMM. 7 days after training no changes were observed in IMM, while the number of new cells decreased in MNM and Ndc in comparison to the control group. These data suggest that newly generated cells in the brain of young chicks are influenced by imprinting procedure, which has opposite short-term and long-term effects. A possible reason for such double action of imprinting in contrast to conventional learning can be its additional stimulation of development of predisposition for features of natural parents.

Overextended RNA:DNA hybrid as a negative regulator of RNA polymerase II processivity.

An eight nucleotide RNA:DNA hybrid at the 3' end of the transcript is required for the stability of the elongation complex (EC) of RNA polymerase II. A non-template DNA strand is not needed for the stability of the EC, which contains this minimal hybrid. Here, we apply a recently developed method for promoter-independent assembly of functional EC of RNA polymerase II from synthetic RNA and DNA oligonucleotides to study the minimal composition of the nucleic acid array required for stability of the complex with RNA longer than eight nucleotides. We found that upon RNA extension beyond 14-16 nt in the course of transcription, non-template DNA becomes essential for maintaining a stable EC. Our data suggest that the overextended RNA:DNA hybrid formed in the absence the non-template DNA acts as a negative regulator of EC stability. The dissociation of the EC correlates with the backsliding of the polymerase along the overextended hybrid. The dual role of the hybrid provides a mechanism for the control of a correct nucleic acid architecture in the EC and of RNA polymerase II processivity.

The 8-nucleotide-long RNA:DNA hybrid is a primary stability determinant of the RNA polymerase II elongation complex.

The sliding clamp model of transcription processivity, based on extensive studies of Escherichia coli RNA polymerase, suggests that formation of a stable elongation complex requires two distinct nucleic acid components: an 8-9-nt transcript-template hybrid, and a DNA duplex immediately downstream from the hybrid. Here, we address the minimal composition of the processive elongation complex in the eukaryotes by developing a method for promoter-independent assembly of functional elongation complex of S. cerevisiae RNA polymerase II from synthetic DNA and RNA oligonucleotides. We show that only one of the nucleic acid components, the 8-nt RNA:DNA hybrid, is necessary for the formation of a stable elongation complex with RNA polymerase II. The double-strand DNA upstream and downstream of the hybrid does not affect stability of the elongation complex. This finding reveals a significant difference in processivity determinants of RNA polymerase II and E. coli RNA polymerase. In addition, using the imperfect RNA:DNA hybrid disturbed by the mismatches in the RNA, we show that nontemplate DNA strand may reduce the elongation complex stability via the reduction of the RNA:DNA hybrid length. The structure of a "minimal stable" elongation complex suggests a key role of the RNA:DNA hybrid in RNA polymerase II processivity.

Functional topography of nascent RNA in elongation intermediates of RNA polymerase.

To determine the dynamics of transcript extrusion from Escherichia coli RNA polymerase (RNAP), we used degradation of the RNA by RNases T1 and A in a series of consecutive elongation complexes (ECs). In intact ECs, even extremely high doses of the RNases were unable to cut the RNA closer than 14-16 nt from the 3' end. Our results prove that all of the cuts detected within the 14-nt zone are derived from the EC that is denatured during inactivation of the RNases. The protected zone monotonously translocates along the RNA after addition of new nucleotides to the transcript. The upstream region of the RNA heading toward the 5' end is cleaved and dissociated from the EC, with no effect on the stability and activity of the EC. Most of the current data suggest that an 8- to 10-nt RNA.DNA hybrid is formed in the EC. Here, we show that an 8- to 10-nt RNA obtained by truncating the RNase-generated products further with either GreB or pyrophosphate is sufficient for the high stability and activity of the EC. This result suggests that the transcript-RNAP interaction that is required for holding the EC together can be limited to the RNA region involved in the 8- to 10-nt RNA.DNA hybrid.

[Antimicrobial and membranolytic activity of sterically hindered phenols]. / Antimikrobnaia i membranoliticheskaia aktivnost' ékranirovannykh fenolov.

Antimicrobial activity of some complicated space phenols (screened) was studied. The compounds had different activities against grampositive bacteria and were inactive against gramnegative microbes. Di-tertiary butyl derivatives of pyrocatechol and resorcin showed the highest activities. The MICs of such derivatives for the collection strains of Bacillus megaterium, Bacillus subtilis and Staphylococcus aureus were 8 to 30 micrograms/ml and exceeded 6-25 times those of the nonsubstituted analogs. The derivatives of pyrocatechol and resorcin impaired the membrane permeability in susceptible intact cells of B.megaterium and S.aureus 209P and had no effect on the membrane permeability of the Escherichia coli resistant cells. In concentrations up to 200 micrograms/ml the nonsubstituted analogs of pyrocatechol and resorcin did not impair the membrane permeability in the intact cells of the above bacteria. Di-tertiary butyl derivatives of pyrocatechol and resorcin had lytic activity with respect to cytoplasmic membranes (protoplasts) of B.megaterium and had no lytic action on E.coli spheroplasts. The antimicrobial spectrum correlated with the membranotropic properties of the compounds. It was suggested that the target of the antimicrobial action of the screened phenols was the bacterial cell cytoplasmic membrane.