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Acoustic neuroma is one of the most common tumors of the posterior cranial fossa. Its removal is always a challenge for the neurosurgeon and the patient. The history of surgery for acoustic neuromas is inextricably linked with the history of neurosurgery in general. The modern surgical community must know history and be able to use it. Only then will the development of surgery lead to the preservation of the quality of life of patients. In the history of surgery for acoustic neuromas, the stages of its development are clearly visible from the description of the clinical picture through the study of the anatomy of the cerebellopontine angle to modern microsurgical removal.

The synthetic approaches to three new AMPA receptor modulators-derivatives of 1,11-dimethyl-3,6,9-triazatricyclo[7.3.1.1 3,11 ]tetradecane-4,8,12-trione-had been developed and all steps of synthesis were optimized. The structures of the compounds contain tricyclic cage and indane fragments necessary for binding with the target receptor. Their physiological activity was studied by radioligand-receptor binding analysis using [ 3 H]PAM-43 as a reference ligand, which is a highly potent positive allosteric modulator of AMPA receptors. The results of radioligand-binding studies indicated the high potency of two synthesized compounds to bind with the same targets as positive allosteric modulator PAM-43 (at least on AMPA receptors). We suggest that the Glu-dependent specific binding site of [ 3 H]PAM-43 or the receptor containing this site may be one of the targets of the new compounds. We also suggest that enhanced radioligand binding may indicate the existence of synergistic effects of compounds 11b and 11c with respect to PAM-43 binding to the targets. At the same time, these compounds may not compete directly with PAM-43 for its specific binding sites but bind to other specific sites of this biotarget, changing its conformation and thereby causing a synergistic effect of cooperative interaction. It can be expected that the newly synthesized compounds will also have pronounced effects on the glutamatergic system of the mammalian brain.

The central effectors of the stress system are greatly interconnected and include, among others, a large group of peptides derived from proopiomelanocortin. In addition to natural corticotropins, a number of artificial molecules that contain some ACTH fragments in their structure are also referred to members of this family. Some of them possess a wide range of biological activity. The molecular mechanism underlying the biological activity of such peptides is partly based on allosteric modulation of various receptors. We analyzed the ability of some biologically active synthetic corticotropins (ACTH(4-7)PGP, ACTH(6-9)PGP, ACTH(7-10)PGP), and glyproline PGPL to affect the GABA-receptor system of rat brain. The effects of the peptides were studied in the isolated plasma membranes of brain cells, as well as after systemic peptide administration in the rat model of acute restraint stress. The delayed effect of stress or preadministration of each of the studied peptides on [ 3 H]GABA binding was different for its high- and low-affinity-specific sites. The studied peptides individually affected the binding of [ 3 H]GABA in their own way. Acute restraint stress caused a decrease in [ 3 H]GABA binding at its low-affine site and did not affected the high-affine site. Preliminary peptide administration did not influence this effect of stress., (© 2023 John Wiley & Sons Ltd.)

Background: Neurophysiological monitoring in surgery for hemifacial spasm has been used since the 1990s, when Moller et al. demonstrated the effectiveness of intraoperative assessment of lateral spread response (LSR) regarding postoperative outcomes. Currently, there are conflicting data on effectiveness and feasibility of this technique. Widespread hemifacial spasm determines the relevance of neurophysiological monitoring in surgical treatment of these patients., Objective: To evaluate the effectiveness of various methods of intraoperative neurophysiological monitoring in surgical treatment of hemifacial spasm regarding early postoperative outcomes., Material and Methods: The study group included 43 patients (8 men and 35 women) aged 26-68 years. We assessed severity of hemifacial spasm using the SMC Grading Scale. All patients underwent vascular decompression of the facial nerve under neurophysiological control: monitoring of transcranial motor evoked potentials from facial muscles (m. orbicularis oculi, m. orbicularis oris, m. mentalis) and recording unilateral LSR. The control group included 23 patients (4 men and 19 women) aged 29-83 years. In this group, facial nerve decompression was performed without neurophysiological control. The effect of neurophysiological monitoring on postoperative outcomes (in-hospital period and 3 postoperative months) after vascular decompression of the facial nerve was assessed using the SMC Grading Scale. We considered severity and incidence of spasms., Results: Thirty-one (72%) patients in the main group had no spasms of mimic muscles at discharge. In the control group, there were no spasms in 15 patients (65%). At the same time, there were fewer Grade I patients in the control group (12%) compared to the main group (26%). Moreover, 27 (66%) and 12 (52%) patients were free from episodes of hemifacial spasm in both groups, respectively. Patients with hemifacial spasm grade I-II comprised 29% in the main group and 34% in the control group. The number of relapses within three months increased in the control group (13%)., Conclusion: Intraoperative monitoring of transcranial motor evoked potentials from the facial muscles and LSR during vascular decompression of the facial nerve increases the efficiency of surgery for hemifacial spasm in early postoperative period. Less number of relapses and lower intensity of hemifacial spasm necessitate neurophysiological monitoring in neurosurgical treatment of these patients.

We report the discovery of a new abscisic acid (ABA) metabolite, found in the course of a mass spectrometric study of ABA metabolism by the rhizosphere bacterium Rhodococcus sp. P1Y. Analogue of (+)-ABA, enriched in tritium in the cyclohexene moiety, was fed in bacterial cells, and extracts containing radioactive metabolites were purified and analyzed to determine their structure. We obtained mass spectral fragmentation patterns and nuclear magnetic resonance spectra of a new metabolite of ABA identified as 1-hydroxy-2,6,6-trimethyl-4-oxo-2-cyclohexene-1-acetic acid, which we named rhodococcal acid (RA) and characterized using several other techniques. This metabolite is the second bacterial ABA degradation product in addition to dehydrovomifoliol that we described earlier. Taken together, these data reveal an unknown ABA catabolic pathway that begins with side chain disassembly, as opposed to the conversion of the cyclohexene moiety in plants. The role of ABA-utilizing bacteria in interactions with other microorganisms and plants is also discussed.

Objective: The aim: Investigation of ultrastructural changes in the elements of rats' duodenal mucosa in norm and exposed to a complex of food additives (monosodium glutamate, sodium nitrite and Ponceau 4R)., Patients and Methods: Materials and methods: 70 rats of the experimental groups was administered 0.6 mg/kg of sodium nitrite, monosodium glutamate at a dose of 20 mg/kg, Ponceau 4R at a dose of 5 mg/kg in 0.5 ml of distilled water once daily per os. The doses of food additives were twice lower the allowable normal rate in food products. Animals were removed from the experiment at 1, 4, 8, 12 and 16 weeks., Results: Results: The effect of the complex of food additives on the mucous membrane of the duodenum was manifested by the development of edema and increased local immune response. In the later stages of observation, dystrophic changes in epithelial cells were determined. Vacuoles were found in the cytoplasm., Conclusion: Conclusions: The use of a complex of food additives led to general ultramicroscopic changes in the mucous membrane of rats' duodenum, triggering the morphological mechanisms of nonspecific inflammation in the form of dystrophic changes and the development of apoptosis.

Histiocytosis is a group of idiopathic diseases accompanied by metabolic disorders and accumulation of metabolic products in histiocytes. Isolated Rosai-Dorfman histiocytosis of central nervous system is observed in less than 5% of cases. The authors report treatment and follow-up of a patient with intracranial Rosai-Dorfman disease. There were symptoms of lesion of the left cerebellopontine angle and epileptic seizures. Preoperative MRI identified two tumors (posterior cranial fossa on the left and right-sided parasagittal neoplasm). The authors carried out total resection of supratentorial tumor, after 3 weeks - subtotal resection of tumor in posterior cranial fossa. No recurrence after total resection was observed. Irradiation of infratentorial tumor with a total focal dose of 50 Gy after 6 months resulted tumor shrinkage throughout 12 months. Radiotherapy with the same dose was repeated throughout subsequent 12-month follow-up period due to progression of this focus. This treatment had a positive effect, but new skull base foci occurred. The authors emphasize the effectiveness of total resection and lower efficiency of subtotal excision combined with radiotherapy.

Syndrome of spontaneous intracranial hypotension is increasingly described in the literature as a multifactorial disease with impairment of the quality of life and risk of mortality. CSF-venous fistula as a cause of intracranial hypotension syndrome is extremely rare and requires complex diagnosis and timely surgical treatment., Objective: We present a 55-year-old patient with acute spontaneous intracranial hypotension and spinal CSF-venous fistula. Literature data are also analyzed., Results: Algorithm for diagnosis and efficacy of microsurgical resection of CSF-venous fistula is demonstrated., Conclusion: Intracranial hypotension following spinal fistula requires careful examination. Accurate understanding of pathophysiological and anatomical features of this disease is necessary to select an effective treatment method.

Hemifacial spasm (HFS) is an involuntary synchronous tonic and/or clonic contraction of mimic muscles following ipsilateral facial nerve dysfunction. The last one is a result of neurovascular conflict between the facial nerve and vessel. Currently, vascular decompression is a pathogenetic treatment modality for primary HFS. Various authors describe postoperative recurrence of HFS, and botulinum toxin therapy remains the only option for these patients. We aimed to describe the efficacy of botulinum toxin therapy in patients with HFS recurrence after surgical vascular decompression. The article presents a female patient with a long-term history of HFS and botulinum toxin therapy (with different formulations). Efficacy of therapy gradually decreased (progressive reduction of intervals between injections). MRI revealed a close relationship between posterior inferior cerebellar artery and roots of acoustic-facial nerves near the brainstem. The patient underwent vascular decompression of the left facial nerve root under intraoperative monitoring with positive postoperative outcome. However, HFS symptoms recurred in 3 days after surgery. Botulinum toxin type A (BTA) injections were resumed with significant positive effect that can be explained by reduction of one of the factors involved into HFS. Thus, patients with HFS recurrence after vascular decompression may benefit from BTA therapy.

The cytotoxicity of doxorubicin (Dox) and its peptide modifications Z-Gly-Pro-Dox and Boc-Gly-Pro-Dox were studied. Tetrahymena pyriformis was used as a test system, which made it possible, due to the short life cycle and high reproduction rate of ciliates, to trace their response to the effects of toxicants over several generations. It was found that peptide modification of the Dox molecule markedly reduces its cytotoxic and cytostatic effect. The Z-Gly-Pro-Dox modification has less cytotoxic and cytostatic effect compared to Boc-Gly-Pro-Dox. When determining the ability of drugs (at a concentration of 100 μM) to prevent bacterial contamination of samples, it was shown that the smallest degree of overgrowth was recorded in the presence of Dox (OD 600nm 81.1). Boc-Gly-Pro-Dox also had a bacteriostatic effect, though less pronounced (OD 600nm 93.8). The degree of overgrowth in the presence of Z-Gly-Pro-Dox was close to that of distilled water. The results obtained on ciliates did not contradict the data obtained in similar studies on mice.

The phytohormone abscisic acid (ABA) plays an important role in plant growth and in response to abiotic stress factors. At the same time, its accumulation in soil can negatively affect seed germination, inhibit root growth and increase plant sensitivity to pathogens. ABA is an inert compound resistant to spontaneous hydrolysis and its biological transformation is scarcely understood. Recently, the strain Rhodococcus sp. P1Y was described as a rhizosphere bacterium assimilating ABA as a sole carbon source in batch culture and affecting ABA concentrations in plant roots. In this work, the intermediate product of ABA decomposition by this bacterium was isolated and purified by preparative HPLC techniques. Proof that this compound belongs to ABA derivatives was carried out by measuring the molar radioactivity of the conversion products of this phytohormone labeled with tritium. The chemical structure of this compound was determined by instrumental techniques including high-resolution mass spectrometry, NMR spectrometry, FTIR and UV spectroscopies. As a result, the metabolite was identified as ( 4RS )-4-hydroxy-3,5,5-trimethyl-4-[( E )-3-oxobut-1-enyl]cyclohex-2-en-1-one (dehydrovomifoliol). Based on the data obtained, it was concluded that the pathway of bacterial degradation and assimilation of ABA begins with a gradual shortening of the acyl part of the molecule.

Arachnoid cysts (AC) are spaces with cerebrospinal fluid covered with arachnoid membrane. Most cysts are supratentorial and only 10-12% of ACs are found in posterior cranial fossa. This disease is usually diagnosed in childhood. In adults, ACs make up 1.4% of all focal lesions. ACs of posterior cranial fossa are often localized behind the cerebellum or in cerebellopontine angle. Most patients with cysts do not have permanent symptoms and should be followed-up. Surgery is indicated for cysts complicated by focal and hydrocephalic-hypertension symptoms. Microsurgical or endoscopic procedures are used. Surgical approach is determined by the closest location of cyst to brain surface. The authors report non-standard surgical approach for giant AC of posterior cranial fossa complicated by obstructive hydrocephalus, intracranial hypertension and visual function impairment. Endoscopic third ventriculostomy was followed by AC fenestration through ventriculostomy. Symptoms disappeared within 6 months after surgery.

Background: Currently, the most dynamic areas in the glutamate receptor system neurobiology are the identification and development of positive allosteric modulators (PAMs) of glutamate ionotropic receptors. PAM-based drugs are of great interest as promising candidates for the treatment of neurological diseases, such as epilepsy, Alzheimer's disease, schizophrenia, etc. Understanding the molecular mechanisms underlying the biological action of natural and synthetic PAMs is a key point for modifying the original chemical compounds as well as for new drug design., Objective: We are trying to elaborate a system of molecular functional screening of ionotropic glutamate receptor probable PAMs., Methods: The system will be based on the radioligand - receptor method of analysis and will allow rapid quantification of new AMPAR probable PAMs molecular activity. We plan to use a tritiumlabeled analogue of recently elaborated ionotropic GluR probable PAM ([3H]PAM-43) as the main radioligand., Results: Here, we characterized the specific binding of the ligand and its ability to potentiate ionotropic GluR currents. The existence of at least two different sites of [3H]PAM-43 specific binding has been shown. One of the above sites is glutamate-dependent and is characterized by higher affinity. "Patchclamp" technique showed the ability of PAM-43 to potentiate ionotropic GluR currents in rat cerebellar Purkinje neurons in a concentration-dependent manner., Conclusion: The possibility of using PAM-43 as a model compound to study different allosteric effects of potential regulatory drugs (AMPAR allosteric regulators) was shown. [3H]PAM-43 based screening system will allow rapid selection of new AMPAR probable PAM structures and quantification of their molecular activity., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Objective: Introduction: Polymeric substances, which are used in medicine, can lead to the development of pathological conditions. Therefore, in toxicological evaluation of polymeric materials for medical purposes the primary task is the creation of the appropriate adequate methods of study. The aim: To studytheacinioftherats'submandibularsalivaryglandsin normalcondition andafter exposureof 1% methacrylate., Patients and Methods: Material andmethods:Were studied 50 white rats during the influence of 1% methacrylate on the mucosa of the oral cavity. Histological sections of the rats'submandibularsalivary glands in normalcondition, on day 14 and 30 of experiment were studied using the UMPT - 7 ultramicrotome of Sumy PA "Selmi"., Results: Results and conclusions:Themorphometric study hasestablishedthat in control group thevaluesof theouterdiameterof thesubmandibularglands' acini, the diameter of the lumen and the height of the acini epithelial cells was 36,27±2,17 µm,9,47±0,63 µm and 14,18±1,05 µm, respectively. Histological specimens showed that the acini cells had a prominent basophilia of the cytoplasm and the basally located nucleus. Numerous large homogeneous granules were located in the apical pole of the cells. After influence of the 1% methacrylat there is an increase in the activity of secretory cells, which is confirmed by an increase in the height of epitheliocytes by 25.04% and is a compensatory metacrylate reaction. The increase in salivation further leads to complete depletion of the secretory apparatus of the seromucosal cells, which is confirmed by a decrease in the outer and inner diameters with a decrease in the height of the mandibular salivary glands acini cells by 24.40%.

Objective: The aim: To determine the dynamics of changes in metric parameters of the duct system of rat submandibular glands in normal conditions and chronic ethanol intoxication., Patients and Methods: Materials and methods: 50 albino outbred rats were involved in the experiment. 10 animals were assigned in the control group, 40 animals - in the experimental group. Animals were sacrificed on 5, 9, 12 and 30 days by overdose of thiopental anesthesia. Pieces of the submandibular glands were embedded into epon-812 according to the conventional technique., Results: Results: On day 5 of the experiment the lumen diameter of intercalated duct reduced by 9,15 % (р <0,05). The lumen diameter of the striated ducts was by 5,29 % significantly greater than the values in controls (р <0,05). The lumen diameter of the granular ducts reduced by 2,45 % (р <0,05). On day 30 of the experiment the height of the epithelial cells of the intercalated ducts was by 8,47 % significantly less (р <0,05), the height of the epithelial cells of the striated ducts was by 12,27 % less (р <0,05) and the height of the epithelial cells of the granular ducts was by 11,96 % less (р <0,05) than the values in controls., Conclusion: Conclusions: No recovery of parameters occurs by day 30 of the experiment, indicating the depletion of the secretory epithelium of the duct system, due to dystrophic changes caused by vascular disorder in the microvasculature.

Aim of this study is to determine the changes in the parameters of the ventricles of the brain and cerebral hemodynamics to improve the diagnosis of mild traumatic brain injury. A decrease in the parameters of the lateral ventricles in combination with diffuse cerebral hypoperfusion was found. Focal disorders of cerebral circulation in the frontal and temporal lobes were registered in patients with brain injury. The algorithm of differential diagnosis of mild concussion and brain injury was developed.

An integrated methodological approach to study the molecular aspects of short regulatory neuropeptides biological mechanism is proposed. The complex research is based on radioligand-receptor method of analysis and covers such points of peptides molecular activity as: specific binding of peptides to brain cells plasmatic membranes, formation of tissue specific synacton, influence of peptides (as allosteric modulators) on functionality of different neuroreceptors as well as delayed in time effects of peptides on receptor-binding activity of well-known neuroreceptor systems. Radiolabeled ligands in such complex study are the one of the best and precision instruments to uncover the molecular mechanism of multiple and multitarget biological effects of regulatory peptides. In this issue we used heptapeptide Semax as a model regulatory peptide, [ 3 H]Ach and [ 3 H]GABA as an effector molecules, and the rat model of stress-induced memory and behavior impairment as a morbid state. We showed the ability of Semax to modulate in a dose-dependent manner [ 3 H]Ach and [ 3 H]GABA specific binding to some of its corresponding receptors as well as to affect the number of [ 3 H]GABA specific binding places on rat neurons plasmatic membranes after complex stress exposure., (© 2019 John Wiley & Sons, Ltd.)

Boc-Gly-Pro-DP, Z-Gly-Pro-DP, LA-Gly-Pro-DP, Boc-Gly-Pro-Srt, Z-Gly-Pro-Srt were synthesized for the first time. The stability of these compounds in the presence of leucine aminopeptidase, carboxypeptidase Y, carboxypeptidase B and proline endopeptidase (PEP) was determined. It turned out that the compounds are stable in the presence of aminopeptidases and carboxypeptidases. In the presence of PEP, dopamine (DP) and serotonin (Srt) are cleaved from the synthesized preparations. Thus, new proline-containing Srt and DP derivatives were obtained, Srt and DP could be gradually released from them. This suggest the possibility of a prolonged action of these biologically active compounds on the vital activity of cells and, consequently, of the whole organism.

A mass spectrometric method has been developed for determining the content of dopamine and serotonin derivatives, which allows evaluating the efficiency of their penetration through artificial membranes depending on the structure of their peptide fragment. In this case, the diffusion of dopamine and serotonin derivatives through the membrane occurred as a result of competitive interactions. It was shown which compounds in this mixture more easily penetrate through artificial membranes. It was found that the most promising in terms of overcoming the BBB are Boc-Pro-Srt and Boc-Pro-DOPA.

New data on peptide drugs have been summarized; their high stability is due to both the introduction of Pro-Gly-Pro in various amino acid sequences and the modification of the glyproline fragment itself. Pro-Gly-Pro-Leu, ACTH(6-9)Pro-Gly-Pro, 5-oxo-Pro-Arg-Pro and 5-oxo-Pro-His-Pro-NH2 were used as proline-containing peptides. Tritiated peptides were obtained: Pro-Gly-Pro-Leu with specific radioactivity of 135 Ci/mmol, ACTH(6-9)Pro-Gly-Pro - 26 Ci/mmol, 5-oxo-Pro-Arg-Pro - 60 Ci/mmol and 5-oxo-Pro-His-Pro-NH2 - 75 Ci/mmol. The concentration of Pro-Gly-Pro-Leu, ACTH(6-9)Pro-Gly-Pro, 5-oxo-Pro-Arg-Pro and 5-oxo-Pro-His-Pro-NH2 in the blood was found to be about 200 times more than in the brain for intranasal administration, and in average 600 times more for intravenous administration. The stability of proline-containing peptides in vitro experiments was determined using different commercially available peptidases (leucine aminopeptidases, dipeptidases, carboxypeptidases B and Y), and using nasal mucus, microsomal fraction of the rat brain (IMPC) and rat blood plasma. During peptidase hydrolysis of Pro-Gly-Pro-Leu, the main metabolites were Gly-Pro-Leu, Pro-Gly-Pro, Gly-Pro and Pro-Gly. For ACTH(6-9)Pro-Gly-Pro, the main metabolites were Phe-Arg-Trp-Pro-Gly-Pro and Trp-Pro-Gly-Pro. In peptidase hydrolysis of 5-oxo-Pro-His-Pro-NH2, the major metabolite was 5-oxo-Pro-His-Pro. It was shown that with different methods of peptides administration the composition of the metabolites formed is different. Based on the data obtained, resistance to enzymatic cleavage of peptides and their metabolic pathways were evaluated. Thus, these new data have shown that the above approaches can be used to prolong the action of glyprolines in living objects. In this case, the degradation of proline-containing peptides occurs mainly not due to the action of proteases, but due to other ways of degradation. In general, the data presented in the review indicate the promise of intranasal way of introducing biologically active peptides into the brain of living organisms.

Aim: The objective of the present study was to elucidate the causes of late diagnostics of vestibular shwannomas based on the results of the analysis of the medical histories of the patients admitted to the Academician N.N. Burdenko National Medical Research Centre of Neurosurgery for the management of this condition., Material and Methods: We undertook the retrospective review of a series of 192 cases of vestibular shwannomas in the patients treated based at the N.N. Burdenko National Medical Research Centre of Neurosurgery in 2015. The study included the analysis of demographic characteristics of the patients as well as their anamnestic and clinical data., Results and Discussion: A total of 55 (29%) patients were found to have small tumours (Samii T1-T3) whereas 137 (71%) ones presented with giant neoplasms including T4a and T4b tumours (in accordance with the Samii classification) in 63 (33%) and 74 (38%) patients respectively. The duration of the disease from the appearance of its first clinical symptoms up to the establishment of the definitive diagnosis was 41 months on the average. 37 (19%) patients appeared to have paid no attention to the unilateral impairment of hearing. 46 (24%) patients applied for the medical assistance to the therapists and neurologists. 56 (29%) patients had remained for a long time under the supervision of the ENT specialists and surdologists based at the local outpatient facilities., Conclusion: More than 2/3 of the examined patients presenting with vestibular shwannomas apply for the medical assistance at the late stages of the disease. Such situation can be attributed to the low level of oncological alertness among the general population and health providers, the poor awareness of the general practitioners and otorhinolaryngologists about this pathology, the unavailability or inefficient application of the modern neurovisualization technologies, in the first place magnetic resonance imaging. The problems encountered in connection with the performance of screening studies give evidence of the necessity of the introduction of up-to-date otoneurological and audiological investigations as well as the neurovisualization techniques into the everyday clinical practice for the comprehensive examination of all the patients suffering from unilateral hearing loss.

Petroclival meningiomas (PCMs) are benign, slowly growing tumors. Surgery still remains the main treatment option for them. The desire for total resection of large extended PCMs often leads to the development or worsening of persistent neurological deficits. This paper presents a review of the world literature devoted to petroclival meningiomas. We discuss the issues of PCM classification, biology, diagnosis, and selection of the optimal algorithm for their treatment.

Hypoglossal schwannoma is a rare tumor this frequency approximately less than 5% all non-vestibular schwannomas. Also, it may be sign of neurofibromatosis type 2. Usually, the tong deviation in side of the tumor is the first symptom of the disease. When the tumor size is increased, bulbar disorders and cervico-occipital pain are develop. MRI is the main method of diagnostic. Until the 1970s, mortality after surgical removal reached 50% and was due to bulbar and respiratory dysfunctions. Nowadays, the cause of death remains the same. After introduction stereotactic radiotherapy into clinical practice total removal is not necessary. The purpose of surgery stay is removal of intracranial part of the tumor and decompression of the brainstem (subtotal removal). Radiotherapy or radiosurgery is performed on the intracanal fragment of the tumor. The case of successful surgical treatment of a patient with hypoglossal schwannoma is presented in this article. Subtotal removal was performed via median suboccipital approach. Radiosurgery is planned for residual part of the tumor, located in the hypoglossal nerve channel.

A forensic medical examination of a corpse, whose right leg was completely separated from the body in the pelvic region during a traffic accident, was conducted. At the time of the accident, the victim was a passenger in the rear seat of a passenger car. The examination failed to establish fault for the circumstances of the injury. From the materials of the criminal case it appears that the car hit a metal guard rail, which 'penetrated' the front of the car through a hole in the damaged part of the grille and crossed the interior of the car between the driver's and passenger's seats. It was concluded that to promptly address the issue of the cause of these kinds of peculiar injuries, the participation of a forensic expert in examining the scene of a traffic accident is necessary.

Objective: Introduction: The state of the segments of the microvasculature, especially exchange one, has a significant effect on the organs' functions. The results of it's research can be objectified by morphometric method. The aim: to determine the dynamics of changes in metric indices of the exchange segment of microvasculature of rats' submandibular glands in normal conditions and in chronic ethanol intoxication., Patients and Methods: Materials and methods: 45 albino rats were involved into study. Intact group (n=5) animals were administered with NaCl isotonic solution 4 times a day directly into the stomach. Experimental group (n=40) animals were administered with 40° ethanol 4 times a day directly into the stomach. Animals were sacrificed on 5, 9, 12 and 30 days by overdose of thiopental anesthesia. Lobules of submandibular glands were embedded into epon-812 according to standard procedure., Results: Results: On day 5 of the experiment the outer diameter of the capillary wall significantly reduced (4,91±0,02 μm), that is 19,5 % less than the values in controls (р<0,05). On day 9 of the experiment it was 15,2 % lower than the value of control group (р>0,05). On day 30 of the experiment the outer capillary diameter was 8 % lower compared to controls (р<0,05)., Conclusion: Conclusions: The early observation showed vasodilatation, confirmed by the constriction of the outer diameter and lumen diameter, accompanied by the thickening of the vascular wall under the influence of chronic ethanol intoxication. The indices did not come to normal values by the 30-th day of the experiment.

Introduction: Radiation therapy of small vestibular schwannomas is quite often used as an effective alternative to surgical treatment. At the same time, 2-10% of patients are detected with radioresistant tumors progressing to varying degrees, which is associated with continued tumor growth. In these cases, a decision on surgical resection or re-irradiation of the tumor is made depending on the neurological symptoms, patient's somatic status, and neuroimaging data. Surgical outcomes and intraoperative findings in pre-irradiated patients have been poorly represented in the literature, for which reason we decided to conduct this study. The paper presents a series of patients with vestibular schwannomas who underwent surgical removal of the tumor after radiotherapy., Material and Methods: A total of 39 patients with vestibular schwannomas after radiotherapy underwent surgery at the Burdenko Neurosurgical Institute in 2007-2017. Of these, 22 patients had a tumor removed after a previously performed combined surgical and radiotherapy treatment (group I), and 17 patients underwent tumor resection after previous radiological treatment (group II). The surgical outcomes were studied depending on various factors, and an analysis of the morphological changes in vestibular schwannomas after radiological treatment was carried out., Results: In group I, the tumor was resected totally in 18% of patients, almost totally in 5% of patients, subtotally in 68% of patients, and partially in 9% of patients. In group II, the tumor was resected totally in 6% of patients, almost totally in 12% of patients, subtotally in 76% of patients, and partially in 6% of patients. We found that post-radiation changes in patients undergoing surgery led to an increase in the response of neurovascular structures to surgical intervention, development of pronounced fibrosis around tumors, and changes in the structure of tumors that became more solid. As a result, surgical morbidity increased, and the patient's quality of life after surgery deteriorated.

Acetyl, oleoyl, arachidonoyl, and docosahexaenoyl derivatives of the Pro-Gly-Pro-Leu peptide with a chemical purity of 99.8% were synthesized. The degradation kinetics of the Pro-Gly-Pro-Leu derivatives under the action of leucine aminopeptidase, nasal mucus, and microsomal fraction of the brain and blood of rats was studied. It was shown that the N-acyl derivatives of Pro-Gly-Pro-Leu proved to be more resistant to the action of leucine aminopeptidase and other enzyme systems. The study of the cytotoxic and anti-inflammatory activity of preparations on the mouse macrophage cell line RAW264.7 showed that acylation with oleic and arachidonic acid makes the peptide cytotoxic with LC50 in the range of 70-15 μM and gives it anti-inflammatory properties with EC50 of 32 and 36 μM, respectively.

Short endogenous peptides represent one of the most important constituents of the mammalian body's general regulatory system. Some synthesized analogs and modified natural peptides (eg, corticotropins) also show high biological activity. Nevertheless, the mechanism of action of regulatory peptides remains unclear. To explain the effects of peptides of intermolecular processes, the hypothesis that a synactonal mechanism underlies the action of regulatory peptides, exemplified by the heptapeptide Semax, has been proposed. Thus, in the total pool of Semax metabolites, which includes the cleavage products of the parental molecule, we can distinguish the functional core, represented by the major metabolic products-peptides HFPGP and PGP. These peptides have their own binding sites with similar although differing characteristics. Together with Semax, they constitute a single complex of bioregulators acting in a certain sequence and in interaction, ie, synacton. It can be assumed that the diverse clinically significant effects of the drug Semax are determined by its synacton. Specific interactions between some tritium-labeled peptides (basic constituents of the Semax synacton) and plasma membranes of neurons have been characterized. Only a few peptides of the Semax synacton showed competitive activity for the Semax binding sites. Fragments comprising 5 amino acid residues (EHFPG and HFPGP) showed the highest competitive activity. We also characterized the processes of specific ligand-receptor interactions of some tritium-labeled corticotropins ([ 3 H-Pro]MEHFPGP, [ 3 H-Pro]HFPGP, and [ 3 H-Pro]PGP) by applying mathematical discriminative models (Scatchard, Hill, Bjerrum, and Lineweaver-Burk plots). So the intermolecular interactions of these peptides with plasma membranes of neuronal brain targets are probably not limited by specific binding at orthosteric sites. The effect of peptides that act in the synacton considerably extends the regulatory potential of the initial molecule., (Copyright © 2016 John Wiley & Sons, Ltd.)

It was shown that the neuroactive peptide 5-oxo-Pro-Arg-Pro (5-oxo-PRP) is detected in the brain in the time interval of 5-120 min after it was intravenously or intranasally administered to rats; the maximum concentration of labeled tripeptide in these modes of administration was observed after 30 and 10 min, respectively. A significant difference in the concentrations of 5-oxo-PRP in the blood and brain (the latter was 50 times lower) during intravenous administration indicates a relatively low permeability of the peptide across the blood-brain barrier. Pharmacokinetic data analysis showed that, when administered intranasally, approximately 45% of the total number of 5-oxo-PRP detectable in the brain in the entire period of study enters via transport from the nasal cavity, and the rest of the peptide enters through the blood-brain barrier from the blood stream. It was found that 5-oxo-PRP in rats is rapidly metabolized forming proteolytic products, mainly amino acids, and degradation products, presumably oxidized these amino acids.

Clinical guidelines are topical systematically developed provisions designed to help the doctor make a decision about a treatment approach in certain clinical situations; they provide information on conducting diagnostic and screening tests, the amount of medical and surgical care, and other aspects of clinical practice. Vestibular schwannomas account for 8% of all intracranial lesions, up to 30% of posterior cranial fossa tumors, and 85% of cerebellopontine angle tumors. The incidence rate of acoustic neuromas is approximately 1 case per 100000 population per year. The paper addresses the issues of classification, diagnosis, and treatment of acoustic neuromas. The guidelines discuss in detail the key aspects of formulation of clinical diagnosis, classification features, definition of the indications for surgical or radiation treatment, and principles of expectant treatment in vestibular schwannomas. The article pays particular attention to surgical treatment of acoustic neuromas and describes the criteria for choosing a surgical approach, use of modern surgical equipment, and stages of tumor resection. On the basis of the accepted clinical classification, we propose the algorithms of action depending on the disease stage, pathological process dynamics, patient's age, and clinical manifestations. The key points of the clinical guidelines rely on evidence-based criteria. The work is intended for neurosurgery practitioners.

We present a series of cases of a rare pathology, intracranial neuroenteric cysts, a review of the international literature, and the experience in treating this pathology., Material and Methods: Seven patients with intracranial neuroenteric cysts underwent surgery at the Neurosurgical Institute in the period between 2000 and 2015., Conclusion: The main and only technique for treatment of intracranial neurenteric cysts is their resection.

We present a rare clinical case of a patient with a malignant peripheral nerve sheath tumor developed from the auditory nerve as well as a literature review, including 30 reported cases of this disease.

Aim: To evaluate and compare the characteristics of the regional cerebral blood flow in patients with mild cerebral concussion or injury using the results of perfusion computed tomography (CT)., Material and Methods: Thirty-eight men, aged 18-35 years, including 21 with concussion and 17 with mild cranial/brain injury (CBI), were examined at the early stage of disease. The control group consisted of 7 age-matched men with non-confirmed CBI., Results and Conclusion: The results of CT-perfusion revealed generalized changes in the hemodynamics. There was a significant increase in the mean time and decrease in the total volume of blood flow through selected regions. Hypoperfusion caused by generalized vasospasm was found in all patients at the early stage of mild CBI. Focal disturbances of cerebral blood flow localized in the poles of the frontal and temporal lobes were determined in patients with mild brain injury compared to the patients with concussion. The use of CT-perfusion can improve the diagnosis of mild CBI.

Background: Various suboccipital approaches are extensively used in modern neurosurgery for treatment of posterior cranial fossa disease. The main patient's positions on the operating table during surgery are half-sitting and lying ones., Material and Methods: The article provides a detailed description and methodology of retrosigmoid suboccipital and median suboccipital approaches in a lying position., Conclusion: The retrosigmoid suboccipital and median suboccipital approaches in a lying position, when used correctly, provide a good view of the operating field with the minimal risk of complications associated with the patient's position on the operating table.

Introduction: Liquorrhea is a condition characterized by cerebrospinal fluid (CSF) leakage from the cranial cavity due to injury to the integrity of the dura mater (DM) and bone structures of the skull base. Surgery for posterior cranial fossa (PCF) lesions distinguishes wound CSF leakage when CSF leaks from a surgical wound as well as basal CSF leakage (nasal liquorrhea and, less often, otoliquorrhea). The main cause of basal CSF leakage is injury (including surgical injury) resulting in a defect in the DM and bone structures (cells of the mastoid process in the case of a suboccipital retrosigmoid approach). There are a variety of DM restoration techniques ranging from DM closure or placement of a synthetic or autologous patch to application of various synthetic adhesives in the form of adhesive compositions (Tissucol) and adhesive substances (TachoComb). This article describes the experience with application of a TachoComb® sponge gained at the 5th Clinical Department of the Burdenko Neurosurgical Institute., Material and Methods: The study included 176 patients with acoustic neurinomas. At the final stage of surgery, all the patients underwent DM reconstruction with a TachoComb® collagen sponge. CSF leakage occurred in 3 (1.7%) patients, with each of them having Koos grade 4 tumor. One (0.56%) patient had wound liquorrhea, and 2 (1.1%) patients had nasal liquorrhea. CSF leakage was managed by placement of a lumbar drain; postoperative wound revision was not required., Conclusion: Using the TachoComb® sponge for DM reconstruction in PCF surgery is an effective way to prevent postoperative CSF leakage, provided that the algorithm of manipulations described in the article is followed.

The kinetics of the content of His-Phe-Arg-Trp-Pro-Gly-Pro (ACTH (6-9)PGP) and its hydrolysis products in the blood and brain of rats in the case of intranasal administration and intravenous injection of tritiated ACTH(6-9)PGP was studied. The parameters of bioavailability of ACTH(6-9)PGP administered intranasally were higher, indicating certain prospects in the intranasal application in clinical practice. We also found that the factor that determines ACTH(6-9)PGP proteolysis in experiments both in vivo and in vitro is aminopeptidases. The main products of ACTH(6-9)PGP during its metabolism in rats are short peptides and amino acids.

The maximum amounts of the thyroliberin in the blood and brain of rats at intranasal and intravenous administration were determined. It is found that rat hippocampal, cortical, and cerebellar membranes contain two types of specific binding sites (high- and low-affinity) for the labeled ligand. It was shown that, at intranasal and intravenous administration, maximum amounts of the thyroliberin were detected in the cerebellum and then in the cortex and hippocampus. The degradation of the thyroliberin in the rat brain and its regions at intranasal and intravenous administration was studied. It is shown that the degree of degradation and the formation of proteolytic products of the thyroliberin is different in different regions of the rat brain.

Aim: To study the dynamics of plasma concentration of stress hormones (ACTH and cortisol) and lactate as well as the integrative stress level indicator at neuroreanimation stage of severe cranial-brain injury., Material and Methods: Authors examined 34 patients with traumatic intracranial hematomas including 19 patients who died during the first two weeks after admission to the hospital and 15 patients who were discharged for outpatient treatment. To assess stress level, we used the indicator of stress level estimated as body mass x 1/3 x heart rate frequency x pulse pressure x 0,000126. Contents of blood plasma ACTH and cortisol were determined using radioimmune method, lactic acid was measured with enzyme colorimetric method. A control group included the indicators of 10 healthy people aged from 24 to 44 years., Results and Conclusion: In the first 24 h, the overstrain of the neuroendocrine system in response to strong stress influence of the trauma was noted in all patients. In patients with fatal outcome, an increase in cortisol in the first 24 h was excessive and lactate level was significantly higher during the observational period compared to the patients with favorable outcome. The peak of mortality was at 1-5 days when the stress level indicators, contents of ACTH, cortisol and lactate reached maximal values indicating the stress-induces overstrain of the hypothalamic- pituitary-adrenal axis and promoting the development of brain tissue hypoxia.

We studied the dependence of the levels of Pro-Gly-Pro-Leu peptide and its metabolites (Gly-Pro-Leu, Pro-Gly-Pro, Gly-Pro and Pro-Gly) from the time of administration in the hippocampus, cerebellum, and cerebral cortex of rats. After intravenous injection of Pro-Gly-Pro-Leu, the maximum concentration of metabolites in the rat brain was found in 20-min sample (0.026% from the amount of introduced labeled tetrapeptide); it was by 2.6 times higher that after intranasal administration. The calculated ratios of the peptide content (AUC) in brain structures for Pro-Gly-Pro-Leu and its metabolites after intranasal and intravenous injection were in most cases >1; hence, the levels of these peptides in the cerebellum, hippocampus, and brain cortex after intravenous injection were slightly higher than after intranasal administration. From these data, content of Pro-Gly-Pro-Leu and its metabolites per 1 g of the cerebellum, hippocampus and cortex was calculated: the maximum concentrations of Pro-Gly-Pro-Leu in the cerebellum, hippocampus, and cortex were 15.63, 18.48, and 2.95 pmol/g, respectively.

We have conducted a course of magnetic laser therapy targeted on the vegetative structures at the neck of the children suffering absence seizures in an attempt to optimize the functioning of the non-specific brain structures. The study has demonstrated that such treatment promotes normalization of the components of the orientation response to sound almost to the level observed in the healthy children. The alpha-index returned to the normal value as well.

Proteolysis of Pro-Gly-Pro-Leu, Pro-Gly-Pro-Gly and Pro-Gly-Pro were studied comparatively to Met-Glu-His-Phe-Pro-Gly-Pro (semax). It is shown that all three peptides are considerably more stable to proteolysis by N-leucine-aminopeptidase (EC 3.4.11.1, Sigma, type VI, 9.2 units/mg), and by enzymes of nasal slime, brain microsomal fractions, and rat blood. Metabolites of the proteolysis showed that semax derives His-Phe-Pro-Gly-Pro only, Pro-Gly-Pro-Leu forms Gly-Pro-Leu, Pro-Gly-Pro and Gly-Pro, Pro-Gly-Pro-Gly gives Pro-Gly-Pro and Gly-Pro, and Pro-Gly-Pro forms Gly-Pro.

Thirty-three patients were studied in the acute stage of severe brain injury, 18 patients died during 24 days in a hospital, 15 patients had survived. The functional status of autonomic, hypophysis-adrenal and immune systems was followed up using variation cardiointervalography, Adrenocorticotropic hormone (ACTH) and cortisol as well as cell immunity parameters were measured. In patients with a fatal outcome, the overstrain of compensatory mechanisms of autonomic supply (mode amplitude, AMo and index of strain, IS) noted in the first day was exhausted to 19-22 days. The hyperreactivity of the adrenocorticoid system was characteristic of all patients. The wavelike character of the changes in mean concentration of cortisol, along with the decrease in ACTH, was observed in patients with a fatal outcome while cortisol and ACTH gradually decreased in survived patients. In patients with a fatal outcome, the helper-induction activity was dramatically inhibited after the short-term elevation. These parameters were correlated with the dynamics of mortality: the first peak of mortality was at the first week, along with the overstrain of the autonomic-endocrine regulation; the second peak was at 21-26 days, it was associated with a sharp reduction of hormone production, "immunological pit" and an exhaustion of the adaptive-compensatory mechanisms of the autonomic nervous system.

Proteolysis of semax (Met-Glu-His-Phe-Pro-Gly-Pro, Sem) and its analogues ([Ala1]Sem, [Gly1]Sem, [Thr1]Sem, [Trp1]Sem) that are differ from semax in substitution of N-terminal Met residue were studied. It is shown that such replacement changes the rate of peptides degradation by N-aminopeptidases (EC 3.4.11.2, Sigma, Type VI, 9.2 units. Akt. / mg). [Ala1]Sem, [Gly1]Sem and [Thr1]Sem semax analogues proved to be more stable to proteolysis than semax (Sem), and their initial product of proteolysis is His-Phe-Pro-Gly-Pro (Sem-5). For triptophan analogue both Glu-His-Phe-Pro-Gly-Pro (Sem-6) and Sem-5 product are formed in similar quantities. It is found that all investigated analogues can be used as inhibitors in Sem proteolysis.