[Keyhole surgery for giant basal brain tumors. Theoretical explanation with an example of trans-eyebrow subraorbital approach]. / Aktual'nost' keyhole-dostupov v khirurgii gigantskikh opukholei osnovaniya golovnogo mozga. Teoreticheskoe obosnovanie na primere chrezbrovnogo supraorbital'nogo dostupa.

BACKGROUND: Improvement of modern neurosurgical technology has given rise to keyhole surgery for a wide range of pathologies. Supraorbital trans-eyebrow approach has been described in detail for small tumors of anterior cranial fossa and suprasellar neoplasms. Can we use this small and less traumatic approach for a more complex tumor extending beyond the suprasellar region? OBJECTIVE: To analyze own experience of surgical treatment of large and giant parasellar tumors via supraorbital approach, to identify the principles of such operations, indications and possible limitations. MATERIAL AND METHODS: There were 58 resections of parasellar tumors via mini-supraorbital approach had been performed between 2016 and 2021 at the 2nd pediatric neurosurgical department. We selected 42 patients with large and giant tumors extending beyond the chiasmal-sellar zone and causing occlusive hydrocephalus (mean volume 44.2 cm3). Preoperative status of patients, postoperative clinical data and logistics of in-hospital treatment were analyzed. RESULTS: Total resection was performed in all cases. No redo surgeries or revisions were required. There were no cases of wound infection, CSF leakage and damage to large vessels. CONCLUSION: We standardized planning of surgeries for large neoplasms considering available knowledge about the nature of diseases, analysis of clinical and X-ray data, goals and objectives of surgery. The reader is offered a theoretical substantiation of applicability of keyhole surgery for chiasmal-sellar tumors on the example of well-known mini-supraorbital approach. We gave certain advices on planning such operations and illustrated clinical examples.

[Tubular retractors for transcranial approaches to intraaxial brain tumors in children]. / Opyt primeneniya tubulyarnykh retraktorov v transkranial'noi khirurgii intraaksial'nykh opukholei golovnogo mozga u detei.

Reduction of surgical trauma associated with approach to deep brain structures including resection of tumors is an urgent direction in development of techniques and technology. OBJECTIVE: To analyze the efficacy and safety of tubular retractors in surgery of deep brain tumors in children. MATERIAL AND METHODS: The study included 17 children with deep brain tumors who underwent surgery between 2020 and 2021. Tubular retractors were used in all cases. The control group consisted of 15 children with a similar disease and standard intraoperative tissue traction technique. All patients underwent MRI of the brain on the first postoperative day. We analyzed severity of traction-induced damage to brain tissue in T2 FLAIR and DWI images. RESULTS: Clinical outcomes and structure of surgical complications were similar in both groups. Tubular retractor turned out to be a tool reducing traction injury. In the main group, postoperative MRI revealed significantly less damage to brain tissue along surgical approach in T2 (edema zone) and DWI (ischemic changes) images.

[PLGA mesh-collagen hybrid scaffold and tissue-engineered product in substitution urethroplasty: experimental validation].

Urethral strictures are a pressing issue in modern medicine. Substitution urethroplasty is considered one of the most effective treatment methods. However, despite the surgery showing good results, many problems remain unresolved, one being substitute material deficiency in extensive or recurrent strictures, as well as in cases requiring multistage surgeries, including those used to treat hypospadias. Graft removal also leaves the donor area prone to diseases and increases the length of surgery leading to a higher risk of intra- and postoperative complications. Tissue engineering (namely tissue-engineered products comprised of scaffolds and cells) may be a useful tool in dealing with these issues. The authors assessed the characteristics of a novel hybrid scaffold created from "reconstructed" collagen and a poly(lactic-co-glycolic acid) mesh. The resulting composite product showed good mechanical properties and functional performance. The hybrid scaffold was non-cytotoxic and provided an adequate base for cell adhesion and proliferation. Biodegradation resulted in the scaffold being replaced by urothelium and urethral mucosa. The newly formed tissues possessed adequate structural and functional properties. Only one rabbit out of 12 developed urethral stricture at the site of scaffold implantation. The above-mentioned facts suggest that the novel hybrid scaffold is a promising tissue-engineered product with potential implication in substitution urethroplasty.

[Influence of the MTHFR gene C677T polymorphism with physical performance and function of cardiovascular system in athletes].

The aim of the was to investigate the interrelation between MTHFR gene C677T polymorphism and morphometric echocardiography and physiologic parameters in male ski racers (n = 23). Genotyping was performed by RFLP. Echocardiography was performed by ultrasound scanner Nemio MX (Toshiba, Japan). We found that the MTHFR C677 allele was associated with low myocardial growth and high physical performance of athletes.

[Autonomous pharmacodynamics of organic nitrates in patients with unstable angina].

The pharmacological test with the use of high-resolution rhythmocardiography for the analysis of cardiac rhythm variability associated with peripheral vegetative regulation of the synoatrial node was applied to study effects of a single dose of organic nitrates (nitroglycerin and mononitrate isosorbide) in 41 patients with unstable angina. Rhythmocardiograms were obtained before and after a morning sublingual dose of nitrates preceding intake of basal drugs. The results suggest negative action of nitrates on peripheral vegetative regulation of pacemaker activity of the synoatrial node.

[Autonomous cardioneuropathy in patients with coronary heart disease].

This paper reports the results of an electron microscopic study of the sinoatrial node in deceased patients with CHD in whom high-resolution rhythmocardiography revealed autonomous cardioneuropathy. Non-specific morphological changes in pacemaker cells of the sinoatrial node (swelling and disintegration of mitochondria, incorporation of calcium and accumulation of lipofuscin in mitochondria) can be regarded as manifestations of ischemic insufficiency of cardiac tissue perfusion. The rhythmocardiograms of such patients showed signs of autonomous cardioneuropathy manifest as the sharply decreased amplitude of all vegetative waves. The spectral power pattern was dominated by inefficient humoral-metabolic regulation due to suppression of protective parasympathetic regulation.

[Free-radical processes in cardiomyopathy and concomitant vibration disease].

Progression from local vibration to cardiovascular pathology in patients with vibration disease is associated with remodeling cardiac and vascular tissues under effect of oxidative stress. Myocardium and nodular tissue are most vulnerable during development of occupational cardiopathy. Alteration of the heart rhythm wave structure is a predictor of remodeling.

[Parameters of hypothalamo-pituitary-adrenal, thyroid and genital systems in patients with occupational allergic dermatosis].

The article deals with results obtained in studying parameters of hypthalamus-pituitary-adrenals, thyroid and genital systems. The studies revealed significant changes of both peripheral and central units in these systems. The authors present some clinical data obtained by endocrinologic and gynecologic examinations.

[Occupational diseases-related autonomic system cardioneuropathy in Chelyabinsk region].

Cardiovascular diseases appear to be the most frequent complication and death cause in patients with various forms of occupational diseases. Autonomous nervous system could play significant role in genesis of those complications.

Possibilities of high-resolution HRV analysis.

OBJECTIVE: The purpose of the study was to present the results of 15-year application in practical cardiology of the method of high-resolution registration and analysis of heart rate variability (HRV) for diagnosis of the cardiovascular pathology. METHODS: Database consists of more than 46 thousand cases with different cardiovascular diseases. Here are shown some peculiarities of the HRV analysis and perspective possibilities of the method, named rhythmocardiography. RESULTS: Experience of rhythmocardiography use in cardiology supposes a wide perspective of this method application for the cardiovascular diagnosis. It allows to define various disregulations of the sinus node pacemaker activity, characterized for every form of the coronary artery disease, cardiac arrhythmias, stages of the hypertension disease, syndrome of autonomic cardioneuropathy, high risk of lethal outcome and etc. The rhythmocardiography may be used in treatment choice, in control of the therapy and studying of the autonomic efficacy of some drugs. CONCLUSION: Thereby, rhythmocardiography is an informative method for diagnosis of the cardiovascular pathology. The high-resolution measurement of HRV and following such computer analysis in time-domain and frequency-domain can be considered highly informative, because of reliable correspondence and comparable RCG-results with data of other studies and clinical symptoms of the diseases.

[Dirofilariasis in the Volgograd region--a new disease in the region]. / Dirofiliarioz v Volgogradskoi oblasti--novoe zabolevanie regiona.

Due to the availability of factors whose reasons have not been studied so far for this area. Volgograd and Volgograd Region should be recognized to be a dirofilariasis-endemic zone. The lack of an actual system of prevention, as well as other objective and subjective factors are responsible for constantly increasing numbers of ill human beings and animals. The disease awaits further thorough studies to reveal the causes of this disease in the area; to elaborate a package of preventive measures, and to improve methods of diagnosis, surgical and medical treatments.

[The cardiac index dynamics of patients after the radical correction of tetralogy of Fallot depending on the level of the pressure-support ventilation (PSV) regimen]. / Dinamika serdechnogo indeksa u bol'nykh posle radikal'noi korrektsii tetraday Fallo v zavisimosti ot urovnia podderzhivaiushchego davleniia rezhima ventiliatsii PSV.

Seventeen patients were examined, reoperated on for correction of Fallot's tetralogy on the open heart after a previous aortopulmonary anastomosis. Pressure support ventilation (PSV) was used in all patients during transfer to spontaneous pressure, making use of different levels of pressure support (20, 15, 13, 10, and 8 mm H2O). Decrease of pressure support from 20-15 mm H2O to 13 mm H2O resulted in a sharp increase of cardiac index. We explain this phenomenon by a drastic increase of the respiratory volume during the use of high PSV levels (20-15 mm H2O), surpassing 1.5-2 times the physiological and age-specific norm; this leads to a sharp increase of the mean intrathoracic pressure, disturbing the cardiovascular function.

[Effects of parents' exposure to genotoxic agents on the degree of maturity of the newborn]. / Vliianie kontakta roditelei s genotoksicheskimi vozdeistviiami na stepen' zrelosti novorozhdennykh.

The maturity of full-term newborns was studied by immunological, biochemical, and ecogenetic methods. The study yielded basic immunochemical and ecogenetic evidence. It shows that chronic intrauterine hypoxia and unfavourable ecogenetic factors apparently influence concurrently and result in severe fetal immaturity.

[Expression of tenascin in lymphoid cells and changes in it upon exposure to low doses of x-rays]. / Ekspressiia tenastsina v limfoidnykh kletkakh i ee izmeneniia pod deistviem malykh doz rentgenovskogo izlucheniia.

The oncofetal protein tenascin was detected in some strains of lymphoid cells: murine myeloma X-63, murine hybridoma MLC-1 and K-48 and T-cell plasmacytoma MOLT-4. This effect was in agreement with the concept that tenascin serves as a marker of cell malignancy; such a concept allows one to use the marker in the studies of X irradiation impact on hybridoma clones. A non-linear correlation was found between the content of tenascin and the irradiation dosage, by using two hybridoma strains. There might be alterations in the expression of tenascin in the cultured lymphoid cells while detecting the genotoxic effect produced by different damaging agents.

Enzyme-linked immunoassay and electrophoretic separation of collagens secreted by cultured skin fibroblasts of patients with Ehlers-Danlos and Marfan syndromes.

A method for the quantitation of the collagen types I, III, IV, and V, synthesized by cultured dermal fibroblasts is described. Collagens precipitated from the culture medium and intracellular collagens were detected by enzyme-linked immunosorbent assays with rabbit polyclonal monospecific antibodies. The assay could detect 10 ng protein per well, and intraassay coefficients of variation were less than 5%. Secreted collagens types I and III were also analysed by electrophoretic separation of [3H]-labelled alpha-chains under nonreducing and reducing conditions. These methods revealed a structural abnormality in one patient with clinical features of Marfan syndrome, and led to the postulation that the abnormality resulted from substitution of cysteine for another amino acid in collagen type I. In other patients an increase in the ratio of collagen type III:type I was detected, which may be secondary to an unknown biochemical defect.

Characteristics of the macromolecular components of the extracellular matrix in human hyaline cartilage at different stages of ontogenesis.

The composition of the collagen and proteoglycan components of the extracellular matrix in human rib cartilage under normal conditions at different stages of ontogenesis (from 7 weeks of intrauterine development to 60 years of age) has been analysed. Polyacrylamide gel electrophoresis of collagen CNBr-peptides has shown the presence of type I collagen in embryonal cartilage and a gradual decrease in the quantity of this component relative to type II collagen with increasing age. Analysis of reducible and mature collagen cross-links revealed traces of lysylpyridinoline in addition to hydroxylysylpyridinoline in human rib cartilage. The increase in the content of mature cross-links during ontogenesis was accompanied by a decrease in the content of dihydroxylysinonorleucine. Electrophoretic analysis of proteoglycan monomers revealed four fractions of different mobility and the ratio of these fractions altered in the course of ontogenesis. An increase in the glucosamine/galactosamine ratio in the core proteins was observed with increase in age of the donors. During electrophoretic analysis of the link protein fraction a protein of molecular mass 200 kDa was found. This protein first appeared after 9 weeks of intrauterine development and was present in the rib cartilage at all subsequent stages of embryogenesis. This protein has been identified as tenascin by immunoblotting.

[Identification of a protein with properties of tenascin in the matrix of embryonal cartilage tissue and in a culture of human embryonal fibroblasts]. / Obnaruzhenie belka so svoistvami tenastsina v matrikse émbrional'noi khriashchevoi tkani i v kul'ture émbrional'nykh fibroblastov cheloveka.

A protein with properties of tenascine has been discovered in extracellular matrix of human embryonic cartilage tissue. Its Mr, as determined by electrophoresis in PAAG with SDS, is 205 and 195 kDa. Immunoblotting with monoclonal antibodies raised against tenascine, revealed 2 precipitation bands, which permitted to identify the discovered protein as tenascine. This is the first report of detection of tenascine in rib cartilage matrix of human embryos. A protein identified as tenascine, has been also detected in a culture of human embryonic fibroblasts.

[Use of modified Ayling's method for detection of homozygotes and heterozygotes for phenylketonuria gene]. / Primenenie modifitsirovannogo metoda Eiling dlia vyiavleniia gomo- i geterozigot po genu fenilketonurii.

Activity of phenylalanine hydroxylase from human leukocytes was shown to depend on concentration of phenylalanine and pteridine cofactor; optimal concentrations of the substances were estimated. Using this optimized procedure activity of phenylalanine hydroxylase was studied in leukocytes of homo- and heterozygotes by the phenylketonuria gene as well as in the cells of donors. The mean values of the enzymatic activity were distinctly different in the groups of homo-, heterozygote-bearing patients and in healthy persons, although a slight overlapping of the patterns was observed between the groups. Presence of "atypical" forms of phenylketonuria appears to be responsible for this overlapping. The modified procedure for estimation of phenylalanine hydroxylase activity in leukocytes might be used for differential diagnostics of phenylketonuria.