Introduction Fractures of the proximal femur often occur in elderly and senile patients. Most of them have an unfavorable comorbid background. In this regard, there is a high risk of complications in the postoperative period, which requires the development and implementation of an effective forecasting model in clinical practice designed to take measures to avoid adverse treatment outcomes.

Objective To develop a regression model to predict the probability of lethal outcome within 30 days after surgery in patients with proximal femur fracture.

Material and Methods A retrospective analysis of inpatient case histories of all patients (n = 1222) with proximal femur fracture treated in our hospital in 2018-2019 was performed. A total of 388 cases were selected for the study.

Results After a detailed statistical analysis of the physiological parameters of the patients, four independent factors were identified that increased the risk of death during 30 days following surgery: albumin less than 30 g / l (regression coefficient – 1.742; OR – 5.708, 95% CI – 1.904–17.114, p = 0.002), the presence of diabetes mellitus (regression coefficient – 1.141; OR – 3.130, 95% CI –1.022–9.588, p = 0.046), the presence of acute renal injury (regression coefficient – 3.141; OR – 23.136, 95% CI – 3.886–137.735, p = 0.001), the presence of pneumonia (regression coefficient – 2.130; OR – 8.411, 95% CI – 2.453–28.838, p = 0.001). A regression model for predicting 30-day mortality was developed: the constant regression coefficient was 4.371, the area under the ROC-curve corresponding to the probability of 30-day mortality was 0.841 with 95% CI: 0.732–0.951, model sensitivity and specificity – 78.9 and 81.2%, respectively. After a detailed statistical analysis of the patients' physiological parameters, four independent factors were identified that increase the risk of fatal outcome during the next 30 days after surgery: albumin less than 30 g / l (regression coefficient, 1.742; OR – 5.708, 95% CI (1.904 – 17.114), p = 0.002), presence of diabetes mellitus (regression coefficient – 1.141; OR – 3.130, 95% CI (1.022 – 9.588), p = 0.046), presence of acute renal injury (regression coefficient – 3.141; OR – 23.136, 95% CI (3.886 – 137.735), p = 0.001), presence of pneumonia (regression coefficient – 2.130; OR – 8.411, 95% CI (2.453 – 28.838), p = 0.001). Thereby we developed a regression model to predict 30-day mortality: regression coefficient of the constant was 4.371; area under the ROC curve, corresponding to the dependence of the probability of 30-day mortality, was 0.841 with 95% CI (0.732 – 0.951); model sensitivity and specificity were 78.9 and 81.2%, respectively.

Conclusion Aregression model for predicting mortality in patients with proximal femur fractures based on independent risk factors has a sufficient level of sensitivity and specificity. Its application is possible in practical health care institutions, where patients with trauma are treated.

Introduction Various spondylodesis techniques are used in patients with degenerative diseases of the lumbar spine, but the benefits of these techniques have not been proven.

Objective of the study was to assess the effect of the type of fusion on the incidence of implant instability and related revision surgeries.

Material and Methods This monocentric prospective study included 133 patients with degenerative stenosis of the lumbar spine and confirmed instability of spinal motion segments. Patients underwent transforaminal lumbar interbody fusion (TLIF) with a single cage or direct lateral interbody fusion (DLIF) using standard-sized cages. The conventional open technique was used to supplement TLIF with pedicle screws while percutaneous screw placement was applied in patients treated with DLIF. The duration of follow-up was 18 months. Fisher's exact test was used to assess differences in the incidence of fixator instability based on MSCT and revision interventions. Logistic regression was used to assess the association between potential risk factors and complication rates.

Results The use of DLIF detected by MSCT (32.9 vs 3.6%, p < 0.0001) resulted in a significant reduction in the incidence of screw instability and associated revision interventions (11.8 vs 0%, p = 0.0122). The results of logistic regression, taking into account factors such as bone density and the number of levels at which spondylodesis was performed, confirm the relationship between the reduced incidence of complications and the use of DLIF technology. Conclusion Using DLIF instead of TLIF in patients with degenerative stenosis at the lumbar spine level can lead to a significant reduction in the frequency of screw instability and associated revision surgeries.

Objective To study the copy number of genes-components of signaling cascades involved in DNA repair, cell cycle regulation and apoptosis under the influence of high doses of ionizing radiation.

Material and Мethods The study was carried out on a culture of H1299 non-small cell lung cancer cells. Cell lines were cultured in a Binder incubator (Germany) for 24 h (at 37 °C, 5% CO2 ), and then the groups were divided into therapeutic and control. The first one was irradiated with a NovalisTx, Varian linear accelerator at doses from 18 to 24 Gy, the second was not exposed to radiation. During the study, we monitored cell viability and evaluated apoptotic activity, then each sample was amplified in two iterations. During the study, cell viability was monitored, apoptotic activity was assessed, and then each sample was amplified in two replicates. The relative copy number of genetic loci was determined by Real-Time qPCR (RT-qPCR).

Results When comparing the relative copy number in the genetic loci of the H1299 non-small cell lung cancer cell culture after exposure to a high dose of ionizing radiation, a statistically significant decrease in the relative copy number of the CASP3 and RBBP8 genes was found, which may indicate a decrease in the potential of caspase-mediated tumor repopulation and an increase in the radiosensitivity of tumor cells.

Conclusion Exposure to high doses of ionizing radiation leads to a detrimental effect on tumor cells and allows to overcome one of the mechanisms of radioresistance – tumor cell repopulation.

Introduction An increase in the load on adjacent segments causes changes in the parameters of the spinal-pelvic balance and, as a consequence, the development of the so-called biomechanical «stress». Such pressures are a key link in the pathogenesis of degeneration, and in the presence of clinical and neurological manifestations of the latter and adjacent segment degenerative disease (ASD/ASDd).

Objective of this study was to assess the effect of the parameters of the spinal pelvic balance on the risk of developing ASD/ASDd after dorsal decompression-stabilizing interventions (DDSI).

Material and Methods The study included medical records of patients who underwent DDSI for lumbar spine degenerative diseases. Clinical and instrumental parameters were assessed.

Results Based on the inclusion criteria, 98 patients (48 with signs of ASD/ASDd and 50 without) were included in the study. The average postoperative follow-up period for the respondents was 46.6 ± 9.8 months. If PI/ LL parameters were <10 and the ratio of segmental and global lumbar lordosis (LIV-SI/LI-SI) was 50% or more, the incidence of ASD/ASDd was significantly lower in patients who underwent rigid lumbar stabilization surgery.

Conclusion The values of PI/LL parameters and the ratio of segmental and global lumbar lordosis are obvious risk factors for the development of ASD/ASDd after rigid lumbar spine DDSI.

Objective To compare the clinical effectiveness of various technical and tactical options for surgical treatment of patients with thoracic and lumbar vertebrae fractures with reduced bone mineral density.

Material and Methods The study included 238 patients with the thoracic and lumbar vertebrae fractures with reduced bone mineral density (BMD). The patients were aged between 48 and 85 with T-score –1.5 to –3.5. The study did not include the patients with recurrent or multiple vertebral fractures, with absence of the clear date and fact of fracture in the case history, with neurological complications or polytrauma. The patients had fractures А1.2, А1.3, В1.2, В2.3 according to the classification of Magerl (1992). All patients underwent bisegmental transpedicular fixation (TPF). Group 1 included 68 patients who underwent non-cement augmented transpedicular screw fixation. Group 2 included 170 patients who underwent cement augmented transpedicular fixation. Both groups were divided into 2 subgroups. Subgroups 1.1 and 2.1 included patients operated in two stages. The first stage was TPF and the second stage was anterior corporodesis. Subgroups 1.2 и 2.2 included patients who underwent only TPF. Outcomes and complications were studied. The observation period lasted for not less than 2 years. Correlation analysis was performed between the technique of performing operations and surgical tactics in four subgroups and treatment outcomes.

Conclusion 1. In the treatment of patients with fractures in the thoracic or lumbar spine with reduced BMD, isolated TPF with cemented screw implantation is clinically equivalent to two-stage surgical treatment - TPF with cementless or cemented implantation and anterior corprodesis of injured FPS. 2. In cementless TPF in patients with decreased BMD, anterior corprodesis of the injured VMS is necessary because its failure leads to the loss of anatomical relationship correction achieved during surgery, increase in local kyphosis, and functional maladaptation of patients.

Objective To investigate the relationship between calcium metabolism disorders, stone formation inhibitor levels and stone density in primary and recurrent calcium-oxalate nephrolithiasis.

Material and Methods Sixty nine patients with urolithiasis were examined, their average age was 41,4 ± 9,5 years. Two main groups were distinguished: Group 1 – primary calcium-oxalate nephrolithiasis (PN), Group 2 – recurrent calcium-oxalate nephrolithiasis (RN). Then each group was divided into two subgroups – A and B according to stone density: 500–1000 HU and from 1000–1500 HU, respectively. Stone density was determined by computed tomography (CT). PTH (parathormone), PTHrP (parathyroid hormone related protein), vitamin D, total blood calcium (Ca), ionized blood Ca, total blood protein, Ca and urine pH were also examined. After the examination, patients underwent surgical removal of the stones.

Results It was found that 41.9% of group 1 and 46.9% of group 2 patients had grade I obesity. Average creatinine level in group 2 was 9.7% higher than in group 1 (p < 0.05). Urea level in both groups was not statistically significantly different. Glomerular filtration rate (GFR) was comparable. Groups 2A and 2B had higher PTHrP values (77.61 and 76.98 pg/mL, respectively) combined with relatively high PTH levels (2A – 4.4 pg/mL and 2B – 5.1 pg/mL), relatively low osteopontin concentration (2A – 0.044 pg/ mL, 2B – 1.106 pg/mL), compared to those in group 1 (p < 0.05). Pairwise unidirectional differences between groups 1A and 2A, 1B and 2B were found to correlate positively with density values: for osteopontin: r = 0.992 (p < 0.05); for vitamin D: r = 0.831 (p < 0.05); for blood Ca2+ ions: r = 0.836 (p < 0.05); for urine pH: r = 0.863 (p < 0.05). There was a negative correlation with the daily concentration of urinary calcium ions with the density of concrements: r = -0.663; p < 0.05. The concentration of osteopontin was significantly higher in Group 1B and 2B patients, and it was significantly lower in patients with stones of < 1000 HU density. Higher values of osteopontin concentration were noted in groups 1B and 2B in relation to groups 1A (p < 0.05) and 2A (p < 0.05). The increase of blood Ca2+ ions in patients in groups 1B and 2B in relation to groups 1A (p < 0.05) and 2A (p < 0.05) was also accompanied by higher values of vitamin D.

Conclusion Patients with denser stones showed high values of osteopontin and PTHrP in serum and low values of urinary calcium ions, which may lead to the formation of concrements on the matrix with an organic base. Determination of calcium metabolism makes it possible to predict recurrence of KSD in primary calcium oxalate nephrolithiasis and assess the severity of mineral metabolism disorders in recurrent calcium oxalate nephrolithiasis.

The search for the optimal approach in the treatment of brachiocephalic arteriovenous fistulas is one of the current problems of neurosurgery and vascular surgery. It is important to note that the best prognosis requires timely diagnosis and the earliest possible dissection of the fistula. Also, the method of treatment should have the least negative consequences and a good clinical effect. Previously, surgeons used open surgical vessel ligation with great technical difficulties due to anatomical difficulties of access as well as bleeding. In recent decades, the endovascular approach to treatment has demonstrated advantages over open interventions. Despite the low traumaticity, there is a risk of complications such as untargeted vascular embolization, perioperative stroke, etc. In this article we demonstrate the experience of arterio-venous vertebral artery fistula dissection using an occluder.

Buccal ureteroplasty is considered a rare operation in urology and the indications for its implementation are still not clearly defined. We have described a clinical case of successful replacement of a part of the proximal ureter with a buccal graft in a patient with a single kidney, which was drained for a long time with a nitinol stent, which was subsequently incrustated, which led to the installation of a permanent nephrostomy drainage. The patient had no postoperative complications, the patency of the urinary tract was fully restored.

Background Liquid biopsy is a promising method of diagnosing malignant tumors. It allows determining the level of free circulating tumor cells – micrometastases, tumor DNA, microRNA and exosomes in blood plasma, as well as detecting various genetic changes. This work included a literature review of current scientific publications on liquid biopsy techniques indexed in PubMed.

Objective The aim of the study was to evaluate the efficacy and peculiarities of this technique in comparison with standard methods of morphological verification of oncological diseases, as well as the feasibility of its use in clinical practice. Compared to tissue biopsy LB has the following advantages: simplicity and speed of examination, easy repeatability and low invasiveness, possibility of dynamic monitoring of tumor progression – general clonal transformation as well as the appearance of resistance to treatment. The disadvantages of this method include low sensitivity, difficulty in proper interpretation of biomarkers and determination of their specificity, high risk of false positive and false negative results due to the presence of dormant tumor cells.

Conclusion Currently, liquid biopsy analysis in clinical practice requires standardization and continuous validation.

Accepted: September 3, 2021. Objective of this review is to highlight some aspects of the development and use of cognitive neuroprostheses, such as the technological background for their developing and key modern projects in this field. The literature sources were analyzed and the place of neuroprostheses among other artificial organs and tissues, which are under development or already used in clinical practice, was defined. The main principles of their implementation, structural elements and operating conditions were described. Also, this review presents some examples of diseases which can be corrected by cognitive neuroprostheses. The mechanisms of compensation for the functions of the damaged brain structures when using neuroprostheses are described on the basis of the principles of their interaction with biological neural networks. Descriptions of advanced developments that are currently relevant are given. Moreover, information is provided on the protocols and results of tests on animals and humans of the artificial hippocampus, as well as the results of testing a prosthesis that allows restoring the functions of the prefrontal cortex in animals. The examples considered in the review allow us to conclude that cognitive neuroprostheses are not just a hypothetic concept. They are implemented as specialized experimental solutions for practical clinical issues. Currently, the greatest success has been achieved in restoring the hippocampus functions.