Search Results (194)

The drilling core sampling and chemical analysis method for the quantitative determination of solid mineral deposits has several drawbacks, including a low core drilling efficiency, a high core sampling cost, and a long chemical analysis cycle. In current uranium quantification practices, advanced techniques have been developed to preliminarily determine the formation of uranium content based on the interpretation results of natural $\gamma$-ray total logging. However, such methods still require supplementary core chemical analysis to derive the uranium–radium–radon balance coefficient, which is then used for equilibrium correction to obtain the true uranium content within the uranium-bearing layer. Furthermore, conventional prompt neutron time spectrum logging is constrained by low count rates, resulting in slow logging speeds that fail to meet the demands of practical engineering applications. To address this, this study proposes a uranium quantification method that corrects the natural $\gamma$-ray total logging using prompt neutron time spectrum logging. Additionally, a calibration parameter determination method necessary for quantitative interpretation is constructed. Experimental results from standardized model wells indicate that, in sandstone-type uranium deposits, the absolute error of uranium content is within $\pm 0.002\%\mathrm{eU}$, and the relative error is within $\pm 2.5\%$. These findings validate the feasibility of deriving the uranium–radium–radon balance coefficient without relying on core chemical analysis. Compared with the prompt neutron time spectrum logging method, the proposed approach significantly improves the logging speed while producing results that are essentially consistent with those of natural $\gamma$-ray total logging. It provides an efficient and accurate solution for uranium quantitative interpretation. Full article

Prostate cancer is the second leading cause of cancer-related death in men, with metastatic castration-resistant prostate cancer (mCRPC) and bone metastases representing a critical clinical challenge. Although radium-223 (Ra-223) is approved for treating mCRPC with bone metastases, its efficacy remains limited, necessitating the development of more effective therapies. This study investigates the therapeutic potential of ¹⁷⁷Lu-PSMA-617, a PSMA-targeted radiopharmaceutical, in a murine model of prostate cancer bone metastases. To our knowledge, this is the first study to systematically evaluate ¹⁷⁷Lu-PSMA-617 in an orthotopic bone metastatic prostate cancer model, providing a clinically relevant preclinical platform to assess both imaging and therapeutic performance. We conducted comprehensive preclinical evaluations, including synthesis, stability analysis, cell binding assays, nuclear imaging, in vivo biodistribution, pharmacokinetics, and antitumor efficacy. The synthesis of ¹⁷⁷Lu-PSMA-617 demonstrated high radiochemical yield (99.2%), molar activity (25.5 GBq/μmol), and purity (>98%), indicating high product quality. Stability studies confirmed minimal release of free Lutetium-177, maintaining the compound’s integrity under physiological conditions. In vitro assays showed selective binding and internalization in PSMA-positive LNCaP prostate cancer cells, with negligible uptake in PSMA-negative PC-3 cells. In vivo biodistribution studies demonstrated efficient tumor targeting, with peak uptake in LNCaP tumors (23.31 ± 0.94 %IA/g) at 4 h post-injection. The radiopharmaceutical exhibited favorable pharmacokinetics, with high tumor-to-background ratios (tumor-to-blood, 434.4; tumor-to-muscle, 857.4). Therapeutic efficacy was confirmed by significant survival extension in treated mice (30.7% for 37 MBq and 53.8% for 111 MBq), with median survival times of 34 and 40 days, respectively, compared to 26 days in the control group. Radiation dosimetry analysis indicated a favorable safety profile with a calculated effective dose of 0.127 mSv/MBq. These findings highlight the novelty and translational relevance of using ¹⁷⁷Lu-PSMA-617 in a clinically relevant bone metastasis model, reinforcing its potential as a dual-purpose agent for both targeted therapy and molecular imaging in advanced prostate cancer. Full article

The combustion of hard coal and lignite in power and combined heat and power plants generates significant amounts of coal fly ash (CFA), a waste material with variable properties. CFA naturally contains radionuclides, specifically naturally occurring radioactive materials (NORMs), which pose potential radiological risks to the environment and human health during their storage and utilization, including their incorporation into building materials. Although global research on the radionuclide content in CFA is available, there is a clear gap in detailed and current data specific to Central and Eastern Europe and notably, a lack of a systematic analysis investigating the influence of installed power plant capacity on the concentration profile of these radionuclides in the generated ash. This study aimed to fill this gap and provide crucial data for the Polish energy and environmental context. The objective was to evaluate the concentrations of selected radionuclides (²³²Th, ²²⁶Ra, and ⁴⁰K) in coal fly ash samples collected between 2020 and 2023 from 19 Polish power and combined heat and power plants with varying capacities (categorized into four groups: S1–S4) and to assess the associated radiological risk. Radionuclide concentrations were determined using gamma spectrometry, and differences between groups were analyzed using non-parametric statistical methods, including PERMANOVA. The results demonstrated that plant capacity has a statistically significant influence on the concentration profiles of thorium and potassium but not radium. Calculated radiological hazard assessment factors (Ra_eq, H_ex, H_in, IAED) revealed that although most samples fall near regulatory limits (e.g., 370 Bq kg⁻¹ for Ra_eq), some exceed these limits, particularly in groups S1 (plants with a capacity less than 300 MW) and S4 (plants with a capacity higher than 300 MW). It was also found that the frequency of exceeding the annual effective dose limits (IAEDs) showed an increasing trend with the increasing installed capacity of the facility. These findings underscore the importance of plant capacity as a key factor to consider in the radiological risk assessment associated with coal fly ash. This study’s outcomes are crucial for informing environmental risk management strategies, guiding safe waste processing practices, and shaping environmental policies within the energy sector in Central and Eastern European countries, including Poland. Full article

Introduction: Prostate cancer has been generally resistant to immunotherapy approaches. Radiation can be immunostimulatory, but the extent to which standard prostate cancer treatments induce immune activation has not been well described. The bone-targeted radiopharmaceutical Radium223 (Ra223) has been proposed to enrich immune function, but clinical studies have not fully delineated whether this is true, or by what mechanisms. Enzalutamide has been shown to increase PD-L1 expression on dendritic cells, which could impact immune activation, though the extent to which this is associated with other evidence of immune activation remains uncertain, and combination strategies remain of interest. We performed a randomized phase II trial to evaluate whether Radium223 (Ra223) added to enzalutamide would induce greater immune activation and clinical responses compared to enzalutamide alone in men with metastatic castration-resistant prostate cancer (mCRPC). Methods: Eligible patients were randomized 2:1 to Arm A (enzalutamide 160 mg PO daily + Ra223 55 kBq/kg IV q4 weeks × 6 doses) or Arm B (enzalutamide 160 mg PO daily). Blood was collected at treatment start and during treatment to measure soluble immune checkpoint biomarkers (BTLA, TIM3, HVEM, GITR, LAG3, PD-1, CTLA-4, PD-L1, PD-L2, ICOS). Immunophenotyping by mass cytometry time of flight (CyTOF) was performed to measure peripheral blood mononuclear cell populations before and after treatment. CyTOF was used to determine changes in circulating immune cell population subsets before and after treatment. Biopsies were performed of an active bone metastatic lesion prior to study treatment and after at least 3 months. IHC was subsequently performed to examine changes in immune cell population subsets before and after treatment, and changes in pSTAT3 levels. Results: In total, 30 patients were enrolled, with median age 68. The median duration of follow up was 36 months. PSA responses, PFS, and OS were not significantly different between the two arms; however, the study was not powered for clinical endpoints. Peripheral blood and bone biopsy specimens were analyzed for immune correlatives. Soluble receptor concentrations showed significantly increased expression of PDL-2 in the combination arm, but this was not seen on CyTOF. Otherwise, there were no significant differences in markers of immune activation/exhaustion or immune cell population subsets in the combination arm and enzalutamide monotherapy arm. IHC also did not show a significant difference in immune cell population subsets in bone biopsy specimens before and after treatment in both arms. However, treatment with the combination arm did show significantly increased levels of pSTAT3 (p = 0.04), which was not seen in the enzalutamide monotherapy arm. Conclusions: Our study showed an overall lack of evidence for immune activation or cytokine induction with the combination, which does not make a strong case for combinatorial immunotherapy approaches. However, the combination did induce higher levels of pSTAT3, which has been implicated in radio-resistance. Therefore, the addition of a STAT3 inhibitor to the combination may be of interest to improve efficacy. Full article

This study focused on identifying Th-, Nb-Ta-, Zr-, and REE-bearing minerals with a multivariate statistical approach in alkaline syenite to evaluate their radiological risks, at Nikeiba, Egypt. Through microchemical analyses, by utilizing electron probe microanalysis, horite, microlite, monazite, zircon, columbite, and fergusonite were shown to bear uranium and thorium. These minerals have played an important role in higher radioactive zones in the studied alkaline syenite. REE-minerals comprising bastnäsite, monazite, and fluorite and apatite are well recorded. The total rare earth elements (TREE₂O₃) reveal higher concentrations in bastnäsite than monazite, with averages 74.87 and 63.8 wt%. Ce is considered the most predominant LREE in the analyzed bastnäsite and monazite. The mean values of radionuclide activity concentrations of ²³⁸U, ²³²Th, and ⁴⁰K are 108 ± 20 Bq/kg, 107 ± 9 Bq/kg, and 1255 ± 166 Bq/kg, respectively. Radiological assessments revealed a radium equivalent activity of 357 Bq/kg, below global limits, but an air-absorbed dose rate (166 nGy/h) and annual effective doses (0.81 mSv/y indoors, 0.20 mSv/y outdoors) exceeding safe thresholds. Additionally, the excess lifetime cancer risk (ELCR) was calculated at 0.00071, surpassing the acceptable limit of 0.00029, making these rocks unsafe for construction use. Statistical analyses further underscored the relationships between radionuclide concentrations and associated risks, highlighting the necessity for continuous monitoring and mitigation. Full article

The presence of radionuclides in environmental media, including sediment, is critical in assessing potential health risks due to external gamma radiation. This study investigates the spatial distribution of natural (Ra-226, Th-232, K-40) and artificial (Cs-137) radionuclides in sediment along the Dixcove coastline, Ghana, using High-Purity Germanium (HPGe) gamma-ray spectroscopy. The activity concentrations of Ra-226 ranged from ~14 to ~23 Bq/kg, Th-232 from ~3 to ~10 Bq/kg, and K-40 from ~44 to ~93 Bq/kg, with Cs-137 levels between 0.2 and 1.3 Bq/kg. The highest concentrations of Ra-226 and K-40 were found On-shore, suggesting terrestrial influence, while Th-232 displayed a more uniform distribution. Radiological risk assessments, including radium equivalent activity (Raeq), annual effective dose (AED), and gamma index (Iγ), confirmed that all measured values were below international safety thresholds, indicating no significant health risk. However, the variability in Cs-137 distribution suggests the need for continued monitoring to assess potential long-term contamination trends. A significant discrepancy was observed when comparing Cs-137 values from this study (maximum 1.3 Bq/kg) with previously reported data (~110 Bq/kg), raising concerns about methodological differences or environmental changes, which require further investigation. To address the observed discrepancies between this study and previous investigations, future research should incorporate in situ measurement techniques for a more comprehensive assessment of Cs-137 distribution. Full article

Radium-223 (²²³Ra) was the first radioactive isotope approved for treating castration-resistant prostate cancer (CRPC) with symptomatic bone metastases without visceral metastatic disease. To better understand the action of ²²³Ra, its role in the tumor microenvironment represents a crucial aspect. A literature search was conducted using the PubMed/MEDLINE database and studies regarding the relationship between ²²³Ra and the tumoral microenvironment were considered. The tumoral microenvironment is a complex setting in which complex interactions between cells and molecules occur. Radium-223, as an alpha-emitter, induces double-stranded DNA breaks; to potentiate this effect, it could be used in patients with genetic instability but also in combination with therapies which inhibit DNA repair, modulate the immune response, or control tumor growth. In conclusion, a few studies have taken into consideration the tumoral microenvironment in association with ²²³Ra. However, its understanding is a priority to better comprehend how to effectively exploit ²²³Ra and its action mechanism. Full article

Background/Objectives: The prognostic value of baseline clinical parameters in predicting the survival prolonging effect of Radium-223-dichloride (²²³RaCl₂) for metastatic castration resistant prostate cancer (mCRPC) patients has been the object of intensive research and remains an open issue. This national multicenter study aimed to corroborate the evidence of ten years of clinical experience with ²²³RaCl₂ by collecting data from eight Italian Nuclear Medicine Units. Methods: Data from 581 consecutive mCRPC patients treated with ²²³RaCl₂ were retrospectively analyzed. Several baseline variables relevant to the overall survival (OS) analysis were considered, including age, previous radical prostatectomy/radiotherapy, number of previous treatment lines, prior chemotherapy, Gleason score, presence of lymphoadenopaties, number of bone metastases, concomitant use of bisphosphonates/Denosumab, Eastern Cooperative Oncology Group Performance Status (ECOG-PS), as well as baseline values of hemoglobin (Hb), platelets, Total Alkaline Phosphatase (tALP), Lactate Dehydrogenase (LDH), and Prostate-Specific Antigen (PSA). Data were summarized using descriptive statistics, univariate analysis and multivariate analysis with the Cox model. Results: The median OS time was 14 months (95%CI 12–17 months). At univariate analysis age, the number of previous treatment lines, number of bone metastases, ECOG-PS, presence of lymphadenopathies at the time of enrollment, as well as baseline tALP, PSA, and Hb, were independently associated with OS. After multivariate analysis, the number of previous treatment lines (HR = 1.1670, CI = 1.0095–1.3491, p = 0.0368), the prior chemotherapy (HR = 0.6461, CI = 0.4372–0.9549, p = 0.0284), the presence of lymphadenopathies (HR = 1.5083, CI = 1.1210–2.0296, p = 0.0066), the number of bone metastases (HR = 0.6990, CI = 0.5416–0.9020, p = 0.0059), ECOG-PS (HR = 1.3551, CI = 1.1238–1.6339, p = 0.0015), and baseline values of tALP (HR = 1.0008, CI = 1.0003–1.0013, p = 0.0016) and PSA (HR = 1.0004, CI = 1.0002–1.0006, p = 0.0005) remained statistically significant. Conclusions: In the era of precision medicine and in the landscape of novel therapies for mCRPC, the prognostic stratification of patients undergoing ²²³RaCl₂ has a fundamental role for clinical decision-making, ranging from treatment choice to optimal sequencing and potential associations. This large Italian multicenter study corroborated the prognostic value of several variables, emerging from ten years of clinical experience with ²²³RaCl₂. Full article

Soil samples were collected from a college campus in Taiwan to measure the levels of radionuclides, contributing to the sustainable management of campus environments. A high-resolution HPGe gamma spectrometry system was utilized to measure the activity concentrations of natural radionuclides (²²⁶Ra, ²³²Th, and ⁴⁰K) and artificial radionuclide (¹³⁷Cs). The activity concentrations of ¹³⁷Cs were not detected in the campus soils, suggesting that artificial radionuclides did not contaminate the soil, supporting sustainable soil quality. However, the average concentrations of ²³²Th and ⁴⁰K with mean values of 53.4 ± 5.1 and 504.5 ± 75.4 Bq/kg dw were higher than the global soil average of 45 and 420 Bq/kg dw, respectively. Meanwhile, the average concentration of ²²⁶Ra with a mean value of 30.1 ± 3.0 Bq/kg dw was similar to the global soil average of 32 Bq/kg. The average outdoor absorbed gamma dose rate (D_ex) and annual effective doses (AED_ex), with a mean of 67.2 nGy/h and 82.4 μSv/y, were found to be higher than the average world levels of 57 nGy/h and 70 μSv/y, respectively. Despite these findings, the radium equivalent activity Ra_eq and external hazard index H_ex, with average values of 145.2 Bq/kg and 0.39, respectively, were below the recommended limit values of 370 Bq/kg and 1.0, respectively. This study provides useful information on the background radioactivity of the study campus, which is crucial for developing sustainable strategies to ensure a safe and healthy environment, indicating that there are no radiological hazards in the soil. Full article

Despite treatment, prostate cancer commonly progresses into castration-resistant prostate cancer (CRPC), which remains largely incurable, requiring the development of new interventions. Darolutamide is an orally administered second-generation androgen receptor inhibitor indicated for patients with non-metastatic CRPC or metastatic hormone-sensitive prostate cancer. Here, we evaluated the effect of androgen receptor (AR) inhibition by darolutamide in combination with DNA double-strand-break-inducing targeted radium-223 alpha therapy in vitro and in an intratibial LNCaP xenograft model mimicking prostate cancer metastasized to bone. The results highlight the synergistic antitumor efficacy of darolutamide in combination with radium-223 both in vitro and in vivo. This effect was most likely driven by the downregulation of genes involved in DDR signaling, which was demonstrated in vitro by a gene set enrichment analysis. The combination treatment also reduced pathological tumor-induced effects in bone by decreasing the number of osteoblasts and osteoclasts and reducing abnormal bone formation in tumor-bearing bone. Additionally, it was shown that darolutamide does not affect the uptake of radium-223 into bone tissue. These results support the investigation of darolutamide in combination with radium-223 for the treatment of patients with CRPC metastasized to bone. Full article

The state of Zacatecas (Mexico) is one of the places most affected by pollution from the mining industry. A total of 21 samples from two areas were collected (6 samples from zone A and 15 samples from zone B) to evaluate the level of radioactivity and the degree of contamination with heavy metals. The activity concentration for ²³⁸U and ²³²Th was within typical values but that of ²²⁶Ra exceeded the value of 60 Bq kg⁻¹ in both areas. In some places, the concentration of ⁴⁰K was higher than the world average according to UNSCEAR. The radium equivalent activity Ra_eq and outdoor gamma exposure dose (D) indicated that some sites presented a radiological risk for the population. The excess lifetime cancer risk (ELCR) presented a higher risk than the world average in both sampled areas. Other parameters, such as the radiation index R_i, the external risk index H_ex, and the internal risk index H_in, also indicated that there was a greater risk due to radiation exposure in these areas. In the case of heavy metals, some parameters, such as the EF, the I_geo, and the CF, showed that some places in zone A and zone B were contaminated with As and Pb. However, the concentration of selenium obtained by ICP-MS in the sampled soil was higher than the average in the Earth’s crust, both in mine waste dumps and in unaltered soil, which indicated that the background concentration for selenium in these places is higher than the world average. Full article

Recent advances have broadened the range of therapeutic options for mCRPC, with several new treatments, including novel hormonal therapies (enzalutamide, abiraterone), chemotherapeutic agents (docetaxel, cabazitaxel), immunotherapies (sipuleucel-T), and bone targeting radiopharmaceuticals (radium-223) showing improved clinical outcomes and receiving U.S. Food and Drug Administration approval. These new treatments provide new avenues for improving patient survival and quality of life. Radium-223, a targeted alpha-emitter, specifically targets bone metastases, offering palliative benefits and a potential increase in life expectancy. The integration of radium-223 with other treatments shows promise for managing mCRPC. However, the optimal sequencing and combination of radium-223 with other therapies are still being explored, with various clinical trials investigating new therapeutic approaches. The integration of these therapies, especially to provide more effective, personalized treatment strategies, requires further investigation. A thorough literature review was conducted on current treatments for mCRPC, including chemotherapeutic agents, oral hormonal therapies targeting the androgen receptor axis, immunotherapies, and radium-223. Ongoing clinical trials investigating radium-233 in the context of other therapies for the treatment of mCRPC patients were also reviewed. Further studies should focus on determining the optimal sequencing and dosing and identifying biomarkers that predict treatment response to enhance outcomes of mCRPC patients. This review underlines the rational strategies of combining radium-223 with other therapies, investigating their impact on bone in terms of delaying skeletal-related events, and managing bone disease progression in mCRPC patients. Full article

Introduction: Radium-223 dichloride (radium-223) is a bone-targeting radioisotope therapy that aids in the survival of patients with metastatic castration-resistant prostate cancer (mCRPC) to bones. This study aimed to describe the clinical characteristics and outcomes of patients with mCRPC treated with radium-223 in a real-world setting. Methods: This was a retrospective study of patients with mCRPC treated with radium-223 between 2016 and 2020 at the London Health Sciences Centre in London, Canada. The baseline characteristics between the patients receiving 1–3 and 4–6 treatment cycles were compared using a two-sample t-test and Chi-square test. ANOVA was used to determine if there was a difference in each diagnostic variable per treatment cycle. Kaplan–Meier curves were generated to estimate progression-free survival (PFS) and overall survival in the patients treated with different numbers of cycles. Results: Fifty eligible patients were identified. The median age was 71 years (IQR: 66–76). Most patients (62%) received radium-223 beyond the third-line treatment. The mean number of radium-223 treatments was four. While 60% of the patients received 4–6 injections, 40% received 1–3 injections. Fifty-eight percent (58%) of the patients demonstrated a clinical benefit, with the remainder expressing either disease progression (28%) or stable disease (10%). The patients treated with 4–6 cycles had a delay to disease progression compared to those given 1–3 cycles of radium-223 (F_5,35 = 10.52, p < 0.001). A higher alkaline phosphatase level prior to treatment was associated with a longer PFS (z₃₃ = 2.362, p = 0.018). Treatment-related hospitalization for skeletal-related events was noted in 8% of the patients, and 14% required treatment discontinuation due to hematologic toxicity. Conclusions: This study confirms the safety of radium-223 in patients with mCRPC in a real-world setting. The radium-223 treatment was associated with a clinical benefit in the majority of the patients, particularly in those with higher pre-treatment serum alkaline phosphatase levels. Further studies to identify the predictive biomarkers are warranted to better guide the contemporary use of radium-223. Full article

The assessment of potential radiation hazards in accumulated sediments in aquatic ecosystems is vital for the management and disposal of sediments. Furthermore, preemptive management of radionuclides in terrestrial ecosystems is critical for marine ecosystem conservation. We analyzed the activity concentrations of natural radionuclides (²²⁶Ra,²³²Th, ²³⁸U, and ⁴⁰K) in the surface sediments of major river watersheds in Korea and evaluated the radiation hazards stemming from these activity concentrations. The mean activity concentrations of ²²⁶Ra and ²³⁸U were lower than the global average, whereas those of ²³²Th and ⁴⁰K were higher. The mean values of radium equivalent activity, external hazard index, and internal hazard index calculated from these activity concentrations did not exceed the recommended maximum values. The mean values of absorbed gamma dose rate in air and annual outdoor effective dose rate (AEDR_out) were higher than the global average by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) but remarkably lower than the recommended and background values by the International Commission on Radiological Protection (ICRP) and the Korea Institute of Nuclear Safety (KINS). The contribution of ⁴⁰K and ²³²Th to the AEDR_out mean value was predominant. In conclusion, the surface sediments of major river watersheds in Korea are associated with negligible radiation hazards. These findings provide fundamental data for the management and treatment of sediments in terrestrial and marine ecosystems. Full article

This study analyzes the concentration of radioactive material in the soil near the Maanshan nuclear power plant (NPP). Out of the thirty samples, only one sample was found to have ¹³⁷Cs radioactivity measuring 2.58 Bq/kg. The activity concentrations were 77.2–517.7 Bq/kg, 3.9–31.6 Bq/Kg, and 5.3–39.1 Bq/kg, respectively, with mean values of 344.4 Bq/kg, 18.6 Bq/kg, and 26.5 Bq/kg for ⁴⁰K, ²²⁶Ra, and ²³²Th, respectively. These levels are lower than the global average of soil activity concentrations. The activity concentrations varied, with the highest levels being 7–8 times greater than the lowest levels. Clay content had a positive correlation and sand content had a negative correlation with ⁴⁰K, ²²⁶Ra, and ²³²Th activity concentrations. The activity concentrations followed a normal distribution for ⁴⁰K, ²²⁶Ra, and ²³²Th. The activity ratios for ²³²Th/²²⁶Ra, ⁴⁰K/²³²Th, and ⁴⁰K/²²⁶Ra were 1.43 ± 0.22, 13.1 ± 1.9, and 18.8 ± 4.1, respectively, and ratios show light minerals in the soils. The average values for external hazard indices (H_ex) and radium equivalent activity (Ra_eq) were 0.22 Bq/kg and 83.0 Bq/kg, respectively, both of which are below the recommended limit values of 1.0 Bq/kg and 370 Bq/kg, respectively. The outdoor absorbed dose rate (D_Rex) and annual effective dose equivalent (AED_ex) were 39.0 nGy/h and 47.8 μSv/y, respectively, both of which are lower than the global soil average of 59 nGy/h and 70 μSv/y, respectively. These results indicate that local residents and tourists are not at significant risk of radiological hazards from the soil. The soil activity concentrations can serve as a baseline for continuous monitoring, even after the Maanshan NPP is decommissioned in 2025. Full article