Consequences of ionizing radiation exposure to the cardiovascular system

Tea Polyphenols Mitigate Radiation-Induced Ferroptosis and Intestinal Injury by Targeting the Nrf2/HO-1/GPX4 Signaling Pathway

Radiation-induced intestinal injury (RIII) is a significant concern for cancer patients receiving radiation therapy, as it can lead to complications such as radiation enteropathy. Presently, there are limited options for preventing or treating RIII. Tea polyphenols (TP), found in tea, provide various health benefits, but their antiradiation mechanisms are not fully understood. C57BL/6 mice pre-treated with TP for five days showed a significant improvement in survival rates after being exposed to 10 Gy of 60Co radiation. In the same way, abdominal exposure to 15 Gy of 60Co radiation effectively mitigated radiation-induced colon shortening, damage to intestinal tissues, oxidative stress, the release of inflammatory factors, and disruptions in intestinal microbial balance. In addition, TP treatment lowered the elevation of reactive oxygen species (ROS), iron imbalance, mitochondrial damage, and ferroptosis in IEC-6 cells post-irradiation. Utilizing network pharmacology, molecular docking, and affinity testing, we identified that TP has the capability to target the Nrf2/HO-1/GPX4 signaling pathway, while EGCG, a principal constituent of TP, interacts with HSP90 and mitigates radiation-induced ferroptosis. These findings suggest that TP may serve as a promising therapeutic agent to alleviate radiation-induced intestinal injury (RII).

Monitoring α/β Particles Using a Copper Cluster Scintillator Detector

High-energy radiation is widely used in medicine, industry, and scientific research. Meanwhile, the detection of environmental ionizing radiation is essential to ensure the safe use of high-energy radiation. Among radiation detectors, scintillator detectors offer multiple advantages, including simple structure, high sensitivity, excellent environmental adaptability, and a favorable performance-to-price ratio. However, the development of high-performance scintillators that can provide highly sensitive responses to environmental radiation, especially α/β particles, remains a challenge. In this work, a copper cluster (Cu4I4(DPPPy)2) with excellent water-oxygen stability is prepared using a simple one-pot method at room temperature. Cu4I4(DPPPy)2 not only exhibits excellent X-ray excited luminescence (XEL) under X-ray irradiation but also demonstrates a highly sensitive scintillation response to α/β particles. By integrating Cu4I4(DPPPy)2 with a photomultiplier tube (PMT) and nuclear electronics, an α/β surface contamination monitor is successfully developed. This monitor enables the sensitive detection of excessive α/β particles in real-world environments. The detection frequency and signal intensity of Cu4I4(DPPPy)2 significantly surpass those of commercial scintillator of YAP:Ce, BGO, PbWO4, and anthracene under identical conditions, highlighting the promising application of metal clusters in low-dose environmental radiation detection.

Diselenide-based nanoparticles enhancing the radioprotection to the small intestine of mice

The widespread application of ionizing radiation (IR) in medicine, while beneficial, also poses potential risks that necessitate effective countermeasures. Both 2-(3-aminopropylamino) ethanethiol (WR-1065) and curcumin are recognized as radioprotective agents; however, their clinical utility is hindered by notable shortcomings that could be addressed through reactive oxygen species (ROS)-responsive amphiphilic nanomaterials. We introduced a newly synthesized poly (ethylene glycol) (PEG)-polycaprolactone (PCL) polymer integrated with diselenide bonds and curcumin (HOOC-SeSe-Cur-PEG-SeSe-Cur-PCL, PEG-Cur-SeSe-PCL). The resulting spherical nanoparticles (NPs), which self-assembled from this polymer, were uniform with an average diameter of 118 nm. As a carrier for WR-1065, these NPs demonstrated a loading capacity of 30.9% and an efficacy of 56.7%. Importantly, the degradation of WR-1065 within the NPs was minimal in gastric fluid, decreasing by only approximately 20% over a 6-hour period. The innovative aspect of these NPs is their design to destabilize in ROS-rich environments, facilitating the release of WR-1065 and curcumin. Indeed, the survival rate of mice increased to 50% when these NPs were orally administered prior to exposure to a lethal dose of whole-body irradiation (8 Gy). The radioprotective impact of WR-1065-loaded NPs was evident in the small intestine of irradiated mice, characterized by the amelioration of radiation-induced epithelial damage, reduction of DNA damage, and inhibition of the apoptotic pathway. Collectively, this oral nanocarrier system for WR-1065 and curcumin holds promise as a potential candidate for the prophylaxis and treatment of acute intestinal injuries induced by IR.

Cardiotoxicity following thoracic radiotherapy for lung cancer

Radiotherapy is the standard of care treatment for unresectable NSCLC, combined with concurrent chemotherapy and adjuvant immunotherapy. Despite technological advances in radiotherapy planning and delivery, the risk of damage to surrounding thoracic tissues remains high. Cardiac problems, including arrhythmia, heart failure and ischaemic events, occur in 20% of patients with lung cancer who undergo radiotherapy. As survival rates improve incrementally for this cohort, minimising the cardiovascular morbidity of RT is increasingly important. Problematically, the reporting of cardiac endpoints has been poor in thoracic radiotherapy clinical trials, and retrospective studies have been limited by the lack of standardisation of nomenclature and endpoints. How baseline cardiovascular profile and cardiac substructure radiation dose distribution impact the risk of cardiotoxicity is incompletely understood. As Thoracic Oncology departments seek to expand the indications for radiotherapy, and as the patient cohort becomes older and more comorbid, there is a pressing need for cardiotoxicity to be comprehensively characterised with sophisticated oncology, physics and cardio-oncology evaluations. This review synthesises the evidence base for cardiotoxicity in conventional radiotherapy, focusing on lung cancer, including current data, unmet clinical needs, and future scientific directions.

Feasibility of very low iodine dose aortoiliac CT angiography using dual-source photon-counting detector CT

PURPOSE

To evaluate the feasibility of aortoiliac CT-Angiography (CTA) using dual-source photon-counting detector (PCD)-CT with minimal iodine dose.

METHODS

This IRB-approved, single-center prospective study enrolled patients with indications for aortoiliac CTA from December 2022 to March 2023. All scans were performed using a first-generation dual-source PCD-CT. Images were acquired with fast pitch and full spectral capabilities (collimation 144 × 0.4 mm). The contrast protocol included a mixture of sodium chloride and iodinated contrast agent (Iopromide, total iodine dose: 9.5-9.8 g). Virtual monoenergetic images (VMIs) were reconstructed at 40, 50, 60, and 68 keV. Two blinded radiologists evaluated image quality on a 4-point scale. Attenuation was measured across eight regions in the aorta and iliac arteries, and contrast-to-noise ratio (CNR) was calculated. Statistical comparisons were performed using repeated measures ANOVA and Bonferroni post-hoc tests.

RESULTS

The final cohort consisted of 39 subjects (mean age: 69.6 ± 9.6 years; 30.8 % female). VMI at 40 keV provided significantly higher attenuation: 478 ± 114 HU, compared to 50 keV (331 ± 74 HU), 60 keV (241 ± 51 HU), and 68 keV (190 ± 48 HU) (p < 0.01). This translated in increased CNR for 40 keV reconstructions (11.8 ± 3.9), followed by 50 keV (9.1 ± 3.0), 60 keV (7.0 ± 2.3), and 68 keV (6.1 ± 1.9) (p < 0.01). Subjective image quality was rated excellent at 40 keV (4 [3,4]), though associated with highest noise (38 ± 7.4 HU, p = 0.02).

CONCLUSION

Aortoiliac CTA using dual-source PCD-CT at 40 keV achieved high attenuation and CNR, enabling effective imaging with only 9.8 g of iodine.

Preliminary study on the correlation between thyroid magnetic resonance parameters and radiation dose after radiotherapy for nasopharyngeal carcinoma

Background

Hypothyroidism is a common sequela after radiotherapy for nasopharyngeal carcinoma (NPC). Magnetic resonance imaging (MRI) has gained prominence in thyroid imaging, leveraging its non-ionizing radiation, high spatial resolution, multiparameter and multidirectional imaging. Few previous studies have investigated the evaluation of radiation-induced thyroid injury by MRI.

Methods

MRI and radiotherapy data of 32 patients who were first diagnosed with nasopharyngeal carcinoma in our hospital from April 2015 to April 2024 and underwent radiotherapy in the radiotherapy department were retrospectively collected. Before, during and after radiotherapy, the thyroid morphology was observed on MR images, and the quantitative parameters of size (width, thickness) were measured on T1-weighted images. The signal intensity (SI) of the thyroid gland was measured on T1-weighted imaging (T1WI), T2-weighted imaging (T2WI) and contrast-enhanced T1-weighted imaging. The differences in thyroid parameters at different time points before and after radiotherapy were compared. The correlation between the MRI quantitative parameters of the thyroid and the radiation dose volume of the thyroid and the radiation dose of the pituitary were analyzed.

Results

The width, thickness and volume of the thyroid decreased gradually before, during and 6 and 12 months after radiotherapy. They were negatively correlated with the mean thyroid dose and V50 (p < 0.05), but were not significantly correlated with the maximum and minimum thyroid doses, V30 and V35 (p > 0.05). The T1WI relative signal intensity (RSI), T2WI RSI, and enhanced T1WI RSI of the thyroid gland gradually decreased from before radiotherapy to during radiotherapy and 6 months and 12 months after radiotherapy. The T1WI RSI, T2WI RSI, and enhanced T1WI RSI during radiotherapy and 6 months and 12 months after radiotherapy were negatively correlated with the mean radiation dose, V40, V45, and V50 of the thyroid gland (p < 0.05), but were not significantly correlated with the maximum radiation dose, minimum radiation dose, V30, and V35 of the thyroid gland or the radiation dose of the pituitary gland (p > 0.05).

Conclusion

Quantitative MRI analysis can non-invasively and effectively show the changes in thyroid shape, size and signal intensity in patients with nasopharyngeal carcinoma before and after radiotherapy, which is crucial for early and accurate assessment of thyroid damage, enabling timely treatment to preserve thyroid function.

Assessment of Skills of Caregivers Providing Care for Stroke Patients in East Kazakhstan Region

OBJECTIVES

This study investigated stroke survivors and the characteristics of care management after discharge from hospital to home. The study aimed to identify caregiving difficulties and to assess mastery of skills in implementing recovery activities at home. This was a cross-sectional study.

METHODS

As part of the study, we interviewed 205 informal caregivers caring for stroke survivors. For descriptive statistics, frequencies, mean, medians, and standard deviations were calculated.

RESULTS

Caregivers determined that the main aim was to restore motor activity in 58% (p ≤ 0.021), and the difficulties they most often encounter during caregiving are difficulties related to obtaining information from medical personnel, or not understanding the information received in people under 50 years of age, which were indicated in 47.9% of cases, while in people over 50 years of age, this indicator was 49.5%. The emotional state of the informal caregivers is closely interrelated with the state of stroke survivors. The informal caregivers with a higher education are more resistant to these changes related to the patient's health.

CONCLUSIONS

The informal caregivers in East Kazakhstan face challenges such as inadequate preparation, limited resources, and emotional strain, hindering effective care. High rates of stroke-related impairments highlight the need for better rehabilitation programs and informal caregiver support. Future research should assess intervention programs and support systems.