Remote Radiation Research Articles

The stage-by-stage treatment of critical aortic stenosis and progressive atherosclerosis of the coronary arteries that occurred three decades after radiation therapy for Hodgkin’s lymphoma. Clinical case

Modern treatment programs for Hodgkin’s lymphoma include both drug antitumor therapy and radiation exposure. When conducting remote radiation therapy on the mediastinal lymph nodes, damage to the heart, thoracic aorta and lungs is possible. Such late cardiovascular complications as damage to the valvular apparatus and progressive atherosclerosis of the coronary arteries, leading to obstruction with the subsequent development of coronary heart disease, more often occurred after the use of extended radiation fields and high total focal doses. The article presents a clinical case of a 64-year-old patient with Hodgkin’s lymphoma, who successfully underwent staged cardiac surgery for severe aortic stenosis and progressive atherosclerosis with calcification of the coronary arteries due to radiation exposure.

Superdense Ce3+-activated lutetium silicate scintillating glass for radiation detection

The scintillating photonic glass has the great potential for medicine imaging, nuclear physics, high-energy physics, and national defense. However, the development of the candidate with the high density remains a significant challenge. Herein, the superdense scintillating glasses derived from the Ce3+-activated Lu2O3-SiO2 binary system were successfully fabricated by the strategy of contactless aerodynamic levitation heating under the N2 atmosphere. These glasses are colorless, optical homogeneous, and exhibit superdense density from 6.59 to 7.15 g/cm3, representing the highest density among the fast decay glass systems. The materials present excellent radiation-blocking ability, suitable emission wavelength, and fast response, indicating the promise for fast-event X-ray detection. The micro radiation probe was fabricated by connecting the scintillating glass and the optical fiber. The practical application in remote radiation detection is demonstrated and it exhibits excellent linear response and high signal-to-noise ratio. The results confirm that the fabricated superdense scintillating glass is promising for application in the field of high-energy radiation detection.

Determination of correction factors and correction coefficients for calculations of the absorbed dose

The need to control the dose received by a patient during radiation therapy (RT) is dictated by the quality assurance requirements, which encompass a broad system of organizational and technical measures aimed at achieving consistency and precision in dosimetry measurements. The ultimate goal of using a quality assurance system in RT is to ensure high accuracy in delivering the dose to the tumour, reducing the irradiation volumes of normal, healthy tissues and organs near the target (tumour lesion). It has been established that to enhance the effectiveness of radiation treatment and to reduce the number of complications in subsequent periods, it is necessary to irradiate the local target in the patient’s body with a dose error no greater than ±5%. To control the calculation of the absorbed dose in water using thermoluminescent (TL) dosimeters, irradiated on a gamma therapeutic device for remote radiation therapy, it is necessary to study the influence of various factors (fading, non-linearity of indications, energy dependence, reproduction of the TL signal, presence of a holder) on the magnitude of the TL signal. We have studied and identified various corrective factors and their error values that may affect the calibration of the system (TLD-100 powder (Rexon), thermoluminescent reader PCL-3). In determining the corrective factors to account for the daily drift of the PCL-3 device, the TL signal obtained during the exposure was adjusted based on the control powder indicators. As a control powder, TLD-100 (Rexon) was used, irradiated with an absorbed dose of 2 Gy under standard conditions and aged four months to obtain a stable TL signal.

Advancements in Remote Alpha Radiation Detection: Alpha-Induced Radio-Luminescence Imaging with Enhanced Ambient Light Suppression.

Heavy nuclides like uranium and their decay products are commonly found in nuclear industries and can pose a significant health risk to humans due to their alpha-emitting properties. Traditional alpha detectors require close contact with the contaminated surface, which can be time-consuming, labour-intensive, and put personnel at risk. Remote detection is urgently needed but very challenging. To this end, a candidate detection mechanism is alpha-induced radio-luminescence. This approach uses the emission of photons from radio-ionised excited nitrogen molecules to imply the presence of alpha emitters from a distance. Herein, the use of this phenomenon to remotely image various alpha emitters with unparalleled levels of sensitivity and spatial accuracy is demonstrated. Notably, the system detected a 29 kBq Am-241 source at a distance of 3 m within 10 min. Furthermore, it demonstrated the capability to discern a 29 kBq source positioned 7 cm away from a 3 MBq source at a 2 m distance. Additionally, a 'sandwich' filter structure is described that incorporates an absorptive filter between two interference filters to enhance the ambient light rejection. The testing of the system is described in different lighting environments, including room light and inside a glovebox. This method promises safer and more efficient alpha monitoring, with applications in nuclear forensics, waste management and decommissioning.

Problems of late radiation injuries of the skin and possibilities of their treatment

Currently there is a problem of insufficient effectiveness of treatment of late radiation skin lesions. Possibilities of application of combined schemes of treatment of malignant neoplasms, including radiation therapy, show both good immediate and distant results, life expectancy of patients has increased. However, the issue of such remote local radiation lesions as radiation ulcers also remains relevant. Such lesions in the practice of clinical oncologists usually occur from 1-1,5 months and more after the end of the course of close-focus X-ray therapy for skin cancer. The peculiarity of radiation ulcers is that they heal extremely poorly even by secondary tension. In the pathogenesis of late radiation ulcers, along with disruption of microcirculation, the main role is played by the direct damaging effect of radiation on stem cells and, consequently, suppression of reparative processes. For this reason, such ulcerous defects are characterized by torpidity to drug and surgical treatment. The analysis of modern scientific and practical literature does not fully reveal the peculiarities of the pathogenesis of post-radiation skin lesions leading to the development of radiation ulcers. Researchers have set a goal to search for new modern methods of effective treatment of this pathology. The main purpose of the literature review was to theoretically substantiate the possibilities of including enzyme antioxidants and epidermal growth factor preparations into the complex of pathogenetic treatment of radiation skin ulcers. Superoxide dismutase (SOD) is an active enzyme-antioxidant, it neutralizes excessive free oxygen radicals, and also has a pronounced anti-inflammatory effect by means of oxidative post-radiation stress of skin tissues. Epidermal growth factor promotes cell growth and differentiation of stem cells (SC) involved in ulcer defect regeneration. Pathogenetically justified stepwise application of these drugs will improve the effectiveness of treatment of post-radiation skin ulcers. This paper presents the current information about the pathogenesis of late radiation skin ulcers, the mechanism of action of SOD, epidermal growth factor preparations, as well as the importance of the microenvironment and the homing effect in controlling the links of the pathogenesis of radiation ulcers and the possibility of their reparative regeneration.

Practical aspects of hybrid cooling devices engineering design for HPGe detectors

The article discusses some practical aspects of engineering design associated with the use of Stirling cryocoolers in liquefiers of hybrid cooling devices for HPGe detectors. A feature of hybrid cooling devices is the presence of two modes: the recondensation mode when the cryocooler is operating, and the power interruption mode with a non-renewable LN 2 boil-off. Based on the Thermal Networks Method, models for each mode are proposed, for analyzing heat fluxes between standard components forming the liquefier unit. The proposed models were validated by comparing calculated parameters of the transition process between the two above-mentioned operating modes with those obtained experimentally. It is shown that the minimization of heat gain through the liquefier unit into Dewar for both operating modes of the hybrid cooling device leads to contradictory engineering design requirements. Preliminary conclusions based on the thermal network models are confirmed experimentally on a serial hybrid cooling device, produced by the Baltic Scientific Instruments Company. This resulted in practical recommendations on the choice of condenser position, which depended on operating conditions of hybrid cooling device, for example as a laboratory equipment or as a part of remote radiation monitoring stations.

A retrospective cohort study of the effect of zolendronic acid on mandibular bone optical density in cancer patients

To analyze the density of the mandible in cancer patients during treatment with zoledronic acid. A retrospective cohort study included 45 patients with cancer aged 26-81 years (average age 55±12.88 years), of whom 14 patients had bone metastases (n=14) and took 4 mg of zolendronic acid once every 28 days. The patients underwent standard PET-CT examinations in the «whole body» mode, and the density of the mandible was examined on CT. Radiation therapy was performed by intracavitary administration of strontium 89 chloride; remote radiation therapy with cisplatin radiomodification. In the presence of bone metastases, patients received complex supportive therapy with zolendronic acid. The effect of zolendronic acid on the density of the mandible in the frontal and lateral sections was studied by multidimensional dispersion analysis. Statistically significant differences (p=0.002) were revealed for density indicators according to CT scans of the mandible in the frontal region against the background of zolendronic acid therapy. We attribute the absence of statistically significant differences for the density of the mandible in the lateral sections (p=0.101 and p=0.082) against the background of zolendronic acid therapy to a measurement bias. We attribute the absence of statistically significant differences in density indices against the background of hormonal, radiation, targeted and chemotherapy to the design of the study. Density measurement based on CT examination data can be recommended for use as an additional tool in assessing the effect of zolendronic acid on the density of the mandible. However, the method of measuring the density of the mandible in the lateral sections requires improvement to prevent measurement bias.

Results of Treatment of Patients with Progression of Primary Highly Malignant Brain Gliomas During a Repeated Course of Radiation Therapy. Own Experience

Purpose: To determine the most effective option for repeated radiation therapy in patients with continued growth of primary high-grade brain glioma, taking into account the isodose distribution during the initial course of radiation therapy. Material and methods: As a result of a retrospective analysis, the results of treatment of 100 patients with confirmed progression of high-grade glioma treated at the Chelyabinsk Regional Center for Oncology and Nuclear Medicine in the period from 2010 to 2020 were evaluated. The ratio of men and women was approximately equal (56 men and 44 women). The mean age of patients of both sexes was 47.2±11.9 years. According to the histological conclusion, patients with glioblastomas (GB) prevailed (n = 58), 42 patients were diagnosed with anaplastic astrocytoma (AA). Reoperation was performed in 26 patients. Repeated radiation therapy in an independent variant was performed in 76 patients of them: 17 patients received a course of neuronal therapy in mono mode and in 17 patients in combination with external beam radiation therapy; 23 patients underwent stereotactic radiotherapy (SRS) using the CyberKnife device; in 19 cases, remote radiation therapy. In 24 cases, a chemotherapeutic component was added in addition to radiation treatment. Results: Mean time to relapse was 23 months. The median overall survival (OS) for all patients was 35 months. (DI 26.2–43.7). Indicators of 1-year OS — 85.6 %; 3-year-old — 44.1 %, 5-year-old — 26.5 %. Depending on the type of radiation therapy: the highest progression-free survival (PFS) was found with SPLT and combined photon-neutron therapy (SPNT) as in the group of patients with recurrent EH for 15, 17, and AA 24 and 40 months, respectively. Among the patients included in our study, the majority of patients (42 people) had central recurrences (in which 95 % or more of the volume of the recurrent tumor was within 100-95 % of the initial isodose), 6 had marginal relapses (20 to 80 % of the recurrent volume is within the surface of 95 % isodose), and in 2 cases a distant recurrence was recorded (less than 20 % of the recurrent volume was within 95 % of the isodose). Distant recurrences (marginal and distant) occurred within an average of 12 months, while central recurrences were diagnosed on average 26 months after the end of the course of radiation (chemoradiation) treatment. Conclusion: Thus, when analyzing our data, in all patients with continued growth of primary high-grade brain gliomas, the method of choice for a repeated course of radiation therapy is stereotactic radiation therapy or a combined course of photon-neutron therapy, which allows to overcome the existing radioresistance.

Real-time radiation monitoring of high energy 1.2-GeV synchrotron accelerator using experimental physics and industrial control system

The high energy 1.2-GeV electron accelerator facility’s radiation detection and monitoring system (RDMS) has greatly evolved to be the effective backbone of real-time radiation monitoring for the new light source 3-GeV synchrotron facility. Experimental Physics and Industrial Control System (EPICS), ethernet hardware connections (Optic fibers), and Web-based software interfaces make up the new RDMS framework, built on well-liked network technology. The problems of monitoring i.e., a lot of manpower, poor monitoring accuracy, and inability to monitor continuously in the high radiation dose are eliminated. EPICS, composed of an Input/Output Controller (IOC) and Client Workstations which can communicate with a Local Area Network (LAN), were applied for remote control and radiation measurement. EPICS has been able to transport and store massive amounts of data for large-scale systems with a wide range and high accuracy. The monitoring data were sent to the server through the optic fibers network system, which is more advantages such as no distance restrictions, low attenuation of the signal, faster responding times, and particularly electromagnetic resistance. The data can be accessed anywhere from client monitors with graphical user interfaces. This system is successfully developed and tested for the high energy 1.2-GeV electron accelerator. The RDMS is useful for radiation safety to monitor the radiation dose level during machine operation to protect occupational workers and the public from radiation hazards.

The Role of Remote Stereotactic Body Radiation Therapy in Oligometastatic Disease (General Issues)

С момента первого определения Hellman и Weichselbaum в 1995 г. концепция олигометастатического заболевания является важной областью клинической онкологии. При этом направленная на очаги метастазирования местная абляционная терапия оказалась действенной альтернативой хирургическому подходу. В то же время стереотаксическая аблятивная радиотерапия тела продемонстрировала высокий уровень достижения местного контроля над метастатическим процессом с получением повышенных результатов выживаемости больных, по сравнению с стандартным паллиативным лечением в этих условиях и, в то же время — с низким уровнем токсичности. Вместе с тем, до настоящего времени нет единого мнения относительно терапевтических и прогностических аспектов этого заболевания.

Influence of radiation therapy on the development of complications in single-stage autologous breast reconstruction with a DIEP-flap in breast cancer patients: a retrospective study

Breast reconstruction after complex oncological treatment is an urgent issue due to the high incidence of breast cancer.
 Aim. To analyze the effect of postoperative radiotherapy on the incidence of fat necrosis in single-stage autologous breast reconstruction with a DIEP flap and to evaluate the number of complications in groups with and without postoperative radiotherapy, as well as to determine the risk factors for complications.
 Materials and methods. The medical records of 34 breast cancer patients who underwent one-stage breast reconstruction using a DIEP flap after skin-sparing/subcutaneous mastectomy with and without subsequent radiation therapy were retrospectively studied. The frequency of complications in groups with and without postoperative radiation therapy was assessed.
 Results. Complications developed in 22 (64.7%) patients out of 34. Mild complications developed in 6 (17.6%) patients (divergence of the edges of the postoperative wound of the anterior abdominal wall). Complications of moderate severity developed in 12 (35.3%) patients. Severe complications developed in 4 (11.8%) patients. Out of 22 patients, 6 (17.4%) patients developed areas of fat necrosis after remote radiation therapy in the delayed period, 4 (11.8%) patients, without ESWL, also developed fat necrosis of a part of the flap (areas up to 5 cm). Excision of the area of fat necrosis of the flap was performed in 2 (5.9%) cases under local anesthesia, the rest of the areas of fat necrosis were not excised. The percentage of complications was higher in the group of patients with obesity (20.6%), which indicates that obesity is a risk factor for the development of intraoperative and postoperative complications in patients with simultaneous breast reconstruction with a DIEP flap.
 Conclusion. During radiotherapy after breast reconstruction with a DIEP flap, the incidence of fat necrosis of the flap was higher. Obesity is a risk of intraoperative and postoperative complications in patients with simultaneous increased breast reconstruction with a DIEP flap, since the incidence of complications was in the group of patients with obesity.

Clinical Observation: Assessment of Factors Associated with the Refusal or Termination of Treatment in Patients with Breast Cancer

The study analyzed the clinical observation of the psychological characteristics of a woman diagnosed with breast cancer, who refused part of the proposed therapy, and had no contraindications to start special treatment.Patient Yu.F., born in 1953, diagnosis: cancer of the right breast T1NxM0 ЭР(95 %), ПР(15 %), Her2neu(0), Ki67 (5 %), refused for personal reasons from the surgical treatment proposed at the 1st stage (a written refusal was taken), in connection with which a course of hormone therapy was prescribed, a course of remote radiation therapy according to a radical program. When assessing the psychological profile of the patient, the data obtained demonstrate the presence of paradoxical hyperprotection in the patient who refused part of the treatment. Her psychological profile is similar to the psychological characteristics of women with breast cancer, whose course of the disease ended in death. In a study conducted in 2021, data were obtained on women with a negative outcome of the disease (death), who were convinced of their own luck and in the ability to control what was happening, used a wide range of coping strategies, were more resilient, are optimistic and had a pronounced internality in comparison with women in whom the disease went into stable remission.

Trimodal organ‑preserving treatment of muscle‑invasive bladder cancer

Purpose of the study. Generalization of the world experience of organ‑preserving treatment in muscle‑invasive bladder cancerMaterials and methods. The literature was searched in Medline, Cochrane Library, Elibrary and PubMed systems. Publications describing the modern possibilities of organ‑preserving treatment of muscle‑invasive bladder cancer were included, 58 of which were used to write this review.Results. The review highlights the results of international randomized and significant non‑randomized studies of organ‑preserving treatment in muscle‑invasive bladder cancer. Special attention is paid to the description of a modern combination of treatment methods to achieve its maximum effectiveness while maintaining the quality of life of patients. The analysis of the world literature was carried out, confirming the prospects of organ‑preserving treatment with careful selection of patients.Conclusion. Organ-preserving trimodal therapy for muscle‑invasive bladder cancer remains an alternative treatment strategy. Careful selection of patients plays a key role. The modern approach to trimodal therapy (TMT) is as follows: complete transurethral resection of the bladder (TURB), neoadjuvant or adjuvant chemotherapy, subsequent assessment of the response to treatment (re‑staging with TURB) should be performed; with a complete pathomorphological response, a course of remote radiation therapy up to TFD 60–66 Gy in the case of traditional fractionation (focal radiation therapy and the use of hypofractionation modes are also possible), using modern irradiation technologies (IGRT, IMRT). In case of an incomplete response, the implementation of the radical cystectomy (RCE) is shown. If a relapse occurs during follow‑up after treatment in the volume of TMT, a life‑saving RCE is shown.If the above conditions are met, the oncological results of treatment with TMT are equivalent to those during RCE, but require further study.

Use of 3D planning of HDR brachytherapy in patients with cervical cancer

Background. Combined radiation therapy is the «gold standard» for the treatment of stages IIB-IVA of cervical cancer (cervical cancer). Given the data of statistical indicators of cervical cancer, the study of new approaches to treatment and implementation in clinical practice of modern technologies of radiation therapy of widespread cervical cancer is an extremely important area.
 Purpose – evaluate the benefits of using CT topometric preparation in planning brachytherapy for cervical cancer.
 Materials and Methods. 3D planning of brachytherapy of 24 patients with locally advanced cervical cancer (FIGO IIIB stage), who underwent a radical program of combined radiation therapy (remote radiation therapy with chemical modification with cisplatin followed by HDR-brachytherapy (High dose rate brachytherapy)).
 Results. The paper presents the results of the analysis of differences in brachytherapy planning according to orthogonal images and CT images. The analysis of the influence of the constitutional features of patients revealed that there are differences in the topographic anatomy of the pelvis depending on the surface area of the body. In patients with a body surface area of up to 1,65 m2 , a more intimate fit of the intestine to the target volume of irradiation was noted. No similar planning difficulties were found in patients with a body surface area above 1,65 m2 .
 Conclusions. The use of 3D images in the planning of intracavitary irradiation in patients with cervical cancer provides precision brachytherapy by simultaneously visualizing the irradiated volumes and spatial relationships of the anatomical structures of the pelvis, the introduced endostats and the corresponding volumetric dose distributions.

A Case Report Successful Treatment the Patient with Squamous Esophagus Cancer IV Stage

In this study, we described a clinical case of unoperable squamous carcinoma in the thoracic esophagus, demonstrating the effectiveness of induction chemotherapy followed by independent chemoradiotherapy and brachytherapy in patients with metastatic esophageal carcinoma. The patient was treated with induction chemotherapy, concurrent chemoradiation with weekly carboplatin AUC 2 and paclitaxel 50 mg/m2 and brachytherapy. The most characteristic feature of this clinical case is that the use of brachytherapy in the complex treatment of patients with esophageal carcinoma allows increasing the dose in the target without increasing the risk of complications associated with the escalation of the radiation dose. Brachytherapy can achieve very high rates of local control with a reduction in morbidity, compared with external beam radiation therapy. In most patients, esophageal carcinoma is diagnosed at stages III–IV of the disease. Squamous cell esophageal carcinoma is an aggressive disease that, depending on the prevalence, requires various treatment methods, the search for the optimal one is still ongoing. The main standard of treatment in inoperable patients with squamous cell esophageal carcinoma is self — chemoradiotherapy. However, in patients with unoperable esophageal carcinoma, it is also possible to use induction chemotherapy followed by independent chemoradiotherapy and brachytherapy. The combined use of these methods of treatment in conditions of impossibility of surgical intervention is the method of choice in patients with stage III–IV of the disease. The standard dose of DLT for squamous carcinoma of the esophagus is 50.4 Gy. In the conducted studies, it was shown that the escalation of the dose to the tumor using remote radiation therapy leads to an increase in severe post-radiation injuries and an increase in the frequency of deaths. Induction chemotherapy plus concurrent chemoradiotherapy and brachytherapy to boost tumor, and improves disease control and survival.

Oncology during the New Coronavirus Infection Pandemic.

The COVID-19 pandemic has served as a catalyst for a whole layer of scientific research, including in Russia, where, since 2020, international multicenter studies have been conducted on the impact of the coronavirus infection on the course of oncological diseases, as well as on the development and application of new clinical methods in oncology. In the years 2020–2022, new methods of nuclear medicine based on the targeted effect of ionizing radiation of radiopharmaceuticals began to be actively developed, in particular, new domestic radiopharmaceuticals (RPs) for diagnostics and therapy and methods of intra-arterial radioembolization developed by RPs with 90Y and 188Re of primary and metastatic tumors of various localization. New methods of radiation therapy have been introduced into clinical practice, including remote radiation therapy with “fast” neutrons, which makes it possible to overcome the resistance of a tumor to radiation and drug treatment. In addition, the search for and introduction into clinical practice of new approaches in the field of gene therapy and the use of oncolytic viruses continues. Platforms for complex pharmacogenomic analysis based on global knowledge and deep machine learning are being used in Russia, allowing for the precise selection of the most effective therapy. New multidisciplinary technologies are being developed.

Application of X-ray endovascular occlusion methods in the treatment of prostate cancer

Background. The use of radiotherapy at the treatment of prostate cancer makes it possible to radically cure the neoplasm, but does not reduce infravesical obstruction. With localized prostate cancer, the cause of acute urinary retention is concomitant benign prostatic hyperplasia. X-ray endovascular occlusion of the prostate vessels is based on a decrease in arterial inflow to the prostate gland, which leads to a decrease in its volume and a decrease in the severity of symptoms of obstruction.Aim. To evaluate the effectiveness of the use of X-ray endovascular occlusion of the prostate vessels as a combined treatment for prostate cancer in order to reduce infravesical obstruction.Methods. 15 patients with severe lower urinary tract symptoms scheduled for RT for prostate cancer. Average age is 68 years. Inclusion criteria: Qmax <10 ml/sec, prostate volume >50 cm3, residual urine volume >50 ml. In the conditions of the X-ray operating room, a puncture of the common femoral artery was performed, a microcatheter was carried out to the arteries of the prostate gland and their selective embolization with microparticles with a diameter of 250–500 microns.Results. 1 patient underwent unilateral embolization, 1 patient failed to embolize the arteries on both sides, 1 patient underwent embolization after remote radiation therapy due to the development of obstruction. 2 patients with locally advanced and metastatic prostate cancer without radiotherapy. There were no complications during the treatment and in the postoperative period. All patients noted positive dynamics in assessing the quality of urination. All patients had a decrease in prostate volume and urodynamic parameters (14 to 30 days) after embolization. No significant positive dynamics was achieved in 2 patients.Conclusion. X-ray endovascular occlusion of the prostate vessels is an effective minimally invasive method, can be considered as an independent technique and used to reduce the volume of the prostate in preparation for subsequent radiotherapy. The technique expands the doctor's arsenal when choosing a method for treating prostate cancer, improves the results of treatment, and also has a positive effect on the quality of life.

From bioinformatic screening to low-invasive molecular diagnostics of the cervical tumor sensitivity to radiation therapy.

e17512 Background: Cervical cancer (CC) is one of the most common cancers in women worldwide (4th in frequency). Traditionally, radical hysterectomy or radiation therapy (RT) is used as the standard treatment for early-stage CC, and locally advanced cancers are treated with RT alone. RT results in complete clinical response only in a part of patients due to formation of malignant cell radioresistance. To date, a significant marker list has been identified to predict the response to RT, but none of them has yet entered clinical practice. Therefore, the aim of this study was bioinformation and laboratory screening of molecular markers for low invasive determination of the CC sensitivity to RT. Methods: The study was performed on 300 CC patients (IB1, IB2, IIA1, tumor < 4 cm) and 30 donors without cancer. The Cancer Genome Atlas database was analyzed to identify potential markers. To obtain data from the Genomic Data Commons Data Portal, we used the TCGABiolinks package of the R language in the Rstudio shell. The GISTIC, MutSig and RAE algorithms were used to identify genome regions whose sizes varied (copy number variation, CNV) significantly in a number of tumor samples. The identified markers (CNV) were validated by RT-PCR in extracellular DNA (cfDNA). Blood was collected before the RT. The remote RT was performed on the Varian TrueBeam linear accelerator in VMAT/IMRT mode (TFD 50Gr). Differences were assessed using the Mann-Whitney test (Bonferroni correction was used). Results: RT result analysis allowed to divide patients into 2 groups - sensitive to RT (n = 170, group 1) and resistant (n = 130, group 2). Bioinformation analysis allowed to isolate a number of genes that altered copying and were associated with sensitivity to RT - ERBB2, BIRC2, TRPC6, YAP1, MIR569, LRRC31, SPRED3, MIR4456, CYP1A, CYP1A, FOXO1, ENOX1, EPSTI1, NEK5, KCTD4, SERP2, MIR621, PTEN, SOD2, MIR3939, ATM, CASP1, CASP4, CASP5, CHEK1 and H2AFX. The CNV of these genes was analyzed in cfDNA. In group 1, a decrease (p < 0.05) in the CNV of H2AFX, ATM, CHEK1, LINC00558, LINC00400 and an increase (p < 0.05) in the CNV of CASP1, CASP4, CASP5, CYP1A1, CYP1A2 and GPX4 were found. In group 2, a decrease (p < 0.05) in the CNV of CASP4, CASP5, CYP1A1, YAP1 and MIR569 and an increase in the CNV (p < 0.05) of H2AFX, ATM, CHEK1, ERBB2 and BIRC2 were found in relation to these indicators in donors without cancer. CNV of H2AFX, ATM, CHEK1, ERBB2, BIRC2, MIR569, LINC00400, CASP4, CASP5 and CYP1A1 genes differed statistically significantly (p < 0.005) in 2 groups of CC patients. Conclusions: The markers identified with a combination of bioinformatics and molecular genetic approaches - the CNV of H2AFX, ATM, CHEK1, ERBB2, BIRC2, MIR569, LINC00400, CASP4, CASP5 and CYP1A1 genes in cfDNA - can become the basis for a low invasive determination of the CC sensitivity to RT.

Electromagnetic field controlled domain wall displacement for induced strain tailoring in BaTiO3-epoxy nanocomposite

Failure in an epoxy polymer composite material is prone to initiate by the coalescence of microcracks in its polymer matrix. As such, matrix toughening via addition of a second phase as rigid or/and rubber nano/micro-particles is one of the most popular approaches to improve the fracture toughness across multiple scales in a polymer composite, which dissipates fracture energy via deformation mechanisms and microcracks arrest. Few studies have focused on tailorable and variable toughening, so-called ‘active toughening’, mainly suggesting thermally induced strains which offer slow and irreversible toughening due to polymer’s poor thermal conductivity. The research presented in the current article has developed an instantaneous, reversible extrinsic strain field via remote electromagnetic radiation. Quantification of the extrinsic strain evolving in the composite with the microwave energy has been conducted using in-situ real-time fibre optic sensing. A theoretical constitutive equation correlating the exposure energy to micro-strains has been developed, with its solution validating the experimental data and describing their underlying physics. The research has utilised functionalised dielectric ferroelectric nanomaterials, barium titanate (BaTiO3), as a second phase dispersed in an epoxy matrix, able to introduce microscopic electro-strains to their surrounding rigid epoxy subjected to an external electric field (microwaves, herein), as result of their domain walls dipole displacements. Epoxy Araldite LY1564, a diglycidyl ether of bisphenol A associated with the curing agent Aradur 3487 were embedded with the BaTiO3 nanoparticles. The silane coupling agent for the nanoparticles’ surface functionalisation was 3-glycidoxypropyl trimethoxysilane (3-GPS). Hydrogen peroxide (H2O2, 30%) and acetic acid (C2H4O2, 99.9%) used as functionalisation aids, and the ethanol (C2H6O, 99.9%) used for BaTiO3 dispersion. Firstly, the crystal microstructure of the functionalised nanoparticles and the thermal and dielectric properties of the achieved epoxy composite materials have been characterised. It has been observed that the addition of the dielectric nanoparticles has a slight impact on the curing extent of the epoxy. Secondly, the surface-bonded fibre Bragg grating (FBG) sensors have been employed to investigate the real-time variation of strain and temperature in the epoxy composites exposed to microwaves at 2.45 GHz and at different exposure energy. The strains developed due to the in-situ exposure at composite, adhesive and their holding fixture material were evaluated using the FBG. The domain wall induced extrinsic strains were distinguished from the thermally induced strains, and found that the increasing exposure energy has an instantaneously increasing effect on the development of such strains. Post-exposure Raman spectra showed no residual field in the composite indicating no remnant strain field examined under microwave powers < 1000 W, thus suggesting a reversible strain introduction mechanism, i.e. the composite retaining its nominal properties post exposure. The dielectric composite development and quantifications presented in this article proposes a novel active toughening technology for high-performance composite applications in numerous sectors.

Рак уретры: ошибки диагностики и лечения

Introduction. Urethral cancer is a rare disease that often occurs under the mask of cystitis and urethritis, which can lead to late diagnosis, progression and poor prognosis. Purpose of the study. On the example of a clinical case, to demonstrate the difficulties of diagnosing urethral cancer in women in clinical practice. Materials and methods. The article describes a case of urethral cancer in a 68-year-old woman with complaints of dysuria and difficulty urinating, who was followed up for 3 years with a diagnosis of cystitis, confirmed by cystoscopy. Transvaginal ultrasound examination of the bladder determined the formation of the urethra 29x23x26 mm. A clinical diagnosis was established: «Urotelial papillary-tubular carcinoma of the urethra T1N0M0G3. Chronic urinary retention». Results. The patient underwent electroresection of the tumor and a course of remote radiation therapy with a total focal dose (RRT) of 50 Gy for 45 days. Histopathological conclusion: adenocarcinoma of the urethral mucosa; tumor within the mucosal and submucosal layers. A two-year disease-free survival was noted. Surveillance continues. Conclusions. The early diagnosis and identification of urethral cancer contributes to a better prognosis and survival rate among the patients with this disease.