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2025
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2025
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2025
Introduction. Mine No. 1, operated until 1975, is in the Beshtau mountain range of the Stavropol Territory. The radiation situation and its potential deterioration due to the unsatisfactory condition of the mine dumps is of concern to the public and local administration. The article presents the results of radiation survey of the mine and its dumps and assesses their impact on the exposure of the population and terrestrial biota.
Materials and methods. Gamma survey of the territory and express measurement of radon activity were carried out. For determination of radionuclide activity in soil, sampling with subsequent laboratory analysis was carried out. According to the results of measurements, radiation doses to the population and biota were estimated.
Results. In the dumps of thirteen adits the dose rate values do not exceed 0.6 µSv/h. In the area of other 11 adits there are sites with higher values (up to 5 µSv/h), the soil of which is classified as solid radioactive waste. Values of radon volumetric activity reach 1.5 kBq/m3. When passing the longest route, the effective dose from the inhalation intake of radon will not exceed 3 mSv. The radiation doses to biota are 3 or more times lower than the derived consideration reference level.
Limitations. When comparing the radionuclide content in soil with the criteria for waste classification and estimating biota doses, the traditional assumption of the age-old equilibrium of 234U and 230Th in 238U decay chains was used. Radiation doses were estimated under the assumption of permanent presence of bioobjects on the territory. The chronic exposure dose rate values of 1.0 mGy/day for mammals, vertebrates, and common pine and 10 mGy/day for plants and invertebrates were taken as safe dose levels.
Conclusion. Single visits to Mount Beshtau do not pose a threat to public health. At the estimated values of radiation doses to terrestrial biota there is no information about deterministic effects of ionizing radiation on bioobjects.- Book : 104(1)
- Pub. Date : 2025
- Page : pp.6-12
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2025
Background/Objectives: Oral squamous cell carcinoma (OSCC) is the most common form of head and neck cancer and accounts for over 50,000 new cancer cases annually in the United States. The survival rates are markedly different for localized OSCC versus metastatic disease, for which the five-year survival rate is only 39%. Depending on its pathology and stage at diagnosis, the treatment may involve surgery, radiation, targeted therapy, or conventional chemotherapy. However, there is an unmet need for reliable biomarkers to predict the treatment response or link therapeutic efficacy to tumor progression. We sought to assemble a panel of OSCC tumor progression biomarkers that correlated with the epithelial-to-mesenchymal transition (EMT) and the response to cytotoxic drugs. Methods: We used four cell lines that represented the stepwise progression from normal oral mucosa to dysplastic, invasive, and metastatic OSCC lesions and performed a quantitative analysis via Western blot for putative markers. EMT phenotypes were assessed using wound healing migration assays. Live cell imaging was used to assess drug effectiveness over time. Results: The expression of stratifin, a tumor suppressor gene, is inversely correlated with both tumor progression steps and the expression of the EMT marker N-cadherin. Conversely, the E-cadherin and fibronectin expression was markedly decreased in the advanced-stage OSCC lines. In addition, metastatic Detroit 562 cells exhibited resistance to cell death following docetaxel treatment and showed clear migratory behavior. Conclusions: We describe a molecular signature of advanced and drug-resistant OSCC tumors which encompasses multiple markers, warranting further investigation to establish their utility in predicting clinical outcomes and guiding the treatment options for patients afflicted with oral cancer.- Book : 16(2)
- Pub. Date : 2025
- Page : pp.209-209
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2025
Nowadays, PSMA ligands are widely used for radiotheragnostic purposes in prostate cancer. The synthesis of a PSMA-Bisp conjugate was developed and realized with good yield (overall yield ~58% for the last two steps). All newly synthesized compounds were characterized by physicochemical methods: 1H and 13C NMR, HRMS, and LCMS (for biologically tested samples). Subsequently, Bisp1 (diacetate bispidine ligand), Bisp-alkyne (bifunctional derivative of Bisp1), and its conjugate PSMA-Bisp were labeled by 64Cu in mild conditions. In vitro studies of the labeled conjugate [64Cu]Cu-PSMA-Bisp have shown great stability in model solutions. Finally, [64Cu]Cu-PSMA-Bisp was compared to the well-known PSMA-617 conjugate labeled with 64Cu and they showed similar stability in excess bovine serum (BVS), and at the same time, labeling PSMA-Bisp with 64Cu is characterized by extremely high kinetics in mild conditions, while labeling PSMA-617 with 64Cu requires heating (90 °C). Thus, this conjugate can be incredibly promising for nuclear medicine.- Book : 6(1)
- Pub. Date : 2025
- Page : pp.7-7
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2025
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2025
Background: Radiation therapy-induced oral mucositis is a significant acute side effect in patients with head and neck cancer. Severe mucositis can negatively impact the patient's treatment plan and decrease survival rates. Objectives: This study aimed to evaluate the effect of educational and care interventions on the severity of oral mucositis in patients undergoing radiation therapy for head and neck cancer. Methods: This study was conducted on head and neck cancer patients referred to the chemotherapy and radiotherapy departments of Khatam Al-Anbia and Ali Ibn Abi Talib Hospitals, affiliated with Zahedan University of Medical Sciences, in 2023. A total of 60 participants were selected through convenience sampling and randomly divided into intervention and control groups. Initially, patients in both groups were examined for oral and dental conditions. Oral health was assessed using the Decayed, Missing, and Filled Teeth (DMFT) Index and the Community Periodontal Index of Treatment Needs (CPITN), based on the global WHO standard. The condition of oral mucositis was evaluated upon entry into the study to confirm eligibility. The intervention group received a comprehensive oral and dental care program during their chemotherapy sessions, which consisted of three 45 - 60-minute sessions. In contrast, the control group received routine training. Recognizing the importance of dental health, dental check-ups were performed again before radiotherapy using the DMFT Index, followed by continued monitoring during the radiotherapy period and at the end of radiotherapy to ensure the patients' teeth remained in good condition. At the conclusion of the radiotherapy, the severity of oral mucositis was assessed. Data analysis was performed using SPSS version 27 software, employing paired t-tests, independent t-tests, Fisher’s exact test, Mann-Whitney U, and chi-square tests. A significance level of less than 0.05 was considered statistically significant. Results: An initial examination of oral and dental conditions was conducted using the DMFT Index (Tooth Decay Index) and CPITN Index (Gingival Inflammation Index). Analysis with the independent t-test and Fisher's exact test showed no statistically significant differences between the intervention and control groups (P > 0.46 and P > 0.31, respectively). At the start of radiotherapy, the mean ± standard deviation of the DMFT Index was 16.53 ± 7.56 in the intervention group and 15.13 ± 7.07 in the control group. The independent t-test revealed no significant statistical difference between the two groups (P > 0.46). However, by the end of radiotherapy, a significant difference in the severity of mucositis was observed between the two groups, as determined by the Mann–Whitney U test (P < 0.001). Conclusions: This study underscores the critical role of a collaborative treatment team, including dentists, nurses, and oncologists, in the prevention and management of oral mucositis in patients. By fostering a multidisciplinary approach to patient care, treatment effectiveness, survival rates, and the quality of life for patients can be significantly improved.- Book : 14(1)
- Pub. Date : 2025
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2025
Abstract
Barrier-to-autointegration factor (BAF) associates with mitotic chromosomes and promotes nuclear envelope assembly by recruiting proteins, such as Lamins, required for the reconstruction of the nuclear envelope and lamina. BAF also mediates chromatin anchoring to the nuclear lamina via Lamin A/C. However, the mechanism by which BAF and Lamin A/C bind chromatin and affect the chromatin organization remains elusive. Here we report the cryo-electron microscopy structures of BAF-Lamin A/C-nucleosome complexes. We find that the BAF dimer complexed with the Lamin A/C IgF domain occupies the nucleosomal dyad position, forming a tripartite nucleosomal DNA binding structure. We also show that the Lamin A/C Lys486 and His506 residues, which are reportedly mutated in lipodystrophy patients, directly contact the DNA at the nucleosomal dyad. Excess BAF-Lamin A/C complexes symmetrically bind other nucleosomal DNA sites and connect two BAF-Lamin A/C-nucleosome complexes. Although the linker histone H1 competes with BAF-Lamin A/C binding at the nucleosomal dyad region, the two BAF-Lamin A/C molecules still bridge two nucleosomes. These findings provide insights into the mechanism by which BAF, Lamin A/C, and/or histone H1 bind nucleosomes and influence chromatin organization within the nucleus.- Book : 16(1)
- Pub. Date : 2025
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2025
Atmospheric responses to earthquakes or volcanic eruptions have become an interesting topic and can potentially contribute to future forecasting of these events. Extensive anomalies of the total electron content (TEC) are most often linked with geomagnetic storms or Earth-dependent phenomena, like earthquakes, volcanic eruptions, or nuclear explosions. This study extends rarely discussed, but very frequent, interactions between tectonic plate boundaries and the ionosphere. Our investigations focus on the very frequent occurrence of TEC enhancements not exclusively linked with individual seismic phenomena but located over tectonic plate boundaries. The objective of this study is to provide a review of the global spatiotemporal distribution of TEC anomalies, facilitating the discussion of their potential relations with tectonic activity. We apply a Kriging-based UPC-IonSAT quarter-of-an-hour time resolution rapid global ionospheric map (UQRG) from the Polytechnic University of Catalonia (UPC) IonSAT group for the detection of relative vertical TEC (VTEC) changes. Our study describes global relative and normalized VTEC variations, which have spatial and temporal behaviours strongly indicating their relationship both with geomagnetic changes and the tectonic plate system. The variations in geomagnetic fields, including the storms, disturb the ionosphere and amplify TEC variations persisting for several hours over tectonic plate boundaries, mostly over the diverging ones. The seismic origin of the selected parts of these TEC enhancements and depletions and their link with tectonic plate edges are suspected from their duration, shape, and location. The changes in TEC originating from both sources can be observed separately or together, and therefore, there is an open question about the directions of the energy transfers. However, the importance of geomagnetic field lines seems to be probable, due to the frequent common occurrence of both types of TEC anomalies. This research also proves that permanent observation of global lithosphere–atmosphere–ionosphere coupling (LAIC) is also important in time periods without strong earthquake or volcanic events. The occurrence of TEC variations over diverging tectonic plate boundaries, sometimes combined with travelling anomalies of geomagnetic origin, can add to the studies on earthquake precursors and forecasting.- Book : 17(4)
- Pub. Date : 2025
- Page : pp.614-614
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2025
The application of rubber powder in modified asphalt has garnered significant attention in the field of
road engineering and materials science. This paper discusses the advantages and methods of pretreating rubber powder
in the process of modified asphalt application, including thermal mechanical method, chemical method, microwave
radiation method, supercritical fluid induction, and biological method. By breaking the sulfur cross-linking bonds of
rubber powder, increasing its surface activity, improving its dispersibility and reactivity, rubber powder modified
asphalt shows significant improvements in high-temperature stability, low-temperature crack resistance, storage
stability, and anti-aging performance. Future research should focus on optimizing pretreatment technology, improving
desulfurization efficiency, and enhancing economic and environmental benefits to fully leverage the potential of rubber
powder modified asphalt.- Book : 14(01)
- Pub. Date : 2025
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