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Flavonoids have many biological properties, such as anticancer activity. Chalcones, one of their subunits, attribute their biological activity to their enone part. The presence of dinitrophenyl group in bischalcone because of its radiosensitivity property is important. Radiosensitivity property reduces radiation time in cancer patients and reduces damage to their healthy tissues. In this regard, 2,4-dinitrophenyl bischalcones were synthesized. The presence of 2,4-dinitrobenzaldehyde as a fixed component in synthesis pathway, leads to a reduction in yield of synthesis by common catalysts. Therefore, in this study, for bis-chalone synthesis, we used Graphene Oxide/Fe3O4/L-Proline nanocomposite as a green recoverable bifunctional organocatalyst. This catalyst was recovered simply by applying an external magnet and reused for eight runs. In this research, chalcones and asymmetric bis-chalcones have been synthesized with diverse substitutes in high yields (78–97%). Also, short reaction times (10–82 min), and simple experimental procedures with easy work-up are advantages of the introduced procedure. The synthesized compounds were characterized by melting point and analytical techniques. The chemical structures of synthesized compounds were confirmed by means of IR, 1HNMR, and 13CNMR. [ABSTRACT FROM AUTHOR]

Aim: The diagnosis accuracy of computed tomography (CT) systems and the reliability of calculated Hounsfield Units (HUs) are critical in tumor detection and cancer patients’ treatment planning. This study evaluated the effects of scan parameters (Kilovoltage peak or kVp, milli-Ampere-second or mAS reconstruction kernels and algorithms, reconstruction field of view, and slice thickness) on image quality, HUs, and the calculated dose in the treatment planning system (TPS). Materials and Methods: A quality dose verification phantom was scanned several times by a 16‑slice Siemens CT scanner. The DOSIsoft ISO gray TPS was applied for dose calculations. The SPSS.24 software was used to analyze the results and the P-value <0.05 was considered significant. Results: Reconstruction kernels and algorithms significantly affected noise, signal‑to‑noise ratio (SNR), and contrast‑to‑noise ratio (CNR). The noise increased and CNR decreased by raising the sharpness of reconstruction kernels. SNR and CNR had considerable increments at iterative reconstruction compared with the filtered back‑projection algorithm. The noise decreased by raising mAS in soft tissues. Also, KVp had a significant effect on HUs. TPS-‑calculated dose variations were less than 2% for mediastinum and backbone and less than 8% for rib. Conclusions: Although HU variation depends on image acquisition parameters across a clinically feasible range, its dosimetric impact on the calculated dose in TPS can be neglected. Hence, it can be concluded that the optimized values of scan parameters can be applied to obtain the maximum diagnostic accuracy and calculate HUs more precisely without affecting the calculated dose in the treatment planning of cancer patients. [ABSTRACT FROM AUTHOR]

Purpose: Accurately segmenting head and neck cancer (HNC) tumors in medical images is crucial for effective treatment planning. However, current methods for HNC segmentation are limited in their accuracy and efficiency. The present study aimed to design a model for segmenting HNC tumors in three-dimensional (3D) positron emission tomography (PET) images using Non-Local Means (NLM) and morphological operations. Material and Methods: The proposed model was tested using data from the HECKTOR challenge public dataset, which included 408 patient images with HNC tumors. NLM was utilized for image noise reduction and preservation of critical image information. Following pre-processing, morphological operations were used to assess the similarity of intensity and edge information within the images. The Dice score, Intersection Over Union (IoU), and accuracy were used to evaluate the manual and predicted segmentation results. Results: The proposed model achieved an average Dice score of 81.47 ± 3.15, IoU of 80 ± 4.5, and accuracy of 94.03 ± 4.44, demonstrating its effectiveness in segmenting HNC tumors in PET images. Conclusions: The proposed algorithm provides the capability to produce patient-specific tumor segmentation without manual interaction, addressing the limitations of current methods for HNC segmentation. The model has the potential to improve treatment planning and aid in the development of personalized medicine. Additionally, this model can be extended to effectively segment other organs from limited annotated medical images. [ABSTRACT FROM AUTHOR]

Introduction: Bifunctional radiosensitizer agents in which nitroaromatic moieties are attached through a linker to antineoplastic moieties have demonstrated higher cytotoxicity and radiosensitizer effects than the corresponding counterparts. This study was conducted to investigate the cytotoxicity and radiosensitizer activities of 2, 4-dinitrobenzene as a radiosensitizer moiety which connected to α, β unsaturated aryl ketones against the radioresistant human HT29 colon cancer cells. Methods: A series of bifunctional radiosensitizer derivatives that are composed of electron-affinic 2, 4-dinitrophenyl moiety and thiol reactive unsaturated conjugated ketones were prepared. The designed compounds were synthesized by the reaction of the corresponding 2, 4-dinitrobenzaldehyde, cyclohexanone and different aryl aldehydes. The cytotoxicity and radiosensitizer activity of the tested compounds were examined against HT29 colon cancer cells under aerobic condition. The IC50 value of the tested compounds and percent of survival cells were analyzed by the MTT assay. The clonogenic assay was used to assess the cell viability following treatment with the tested compounds with or without the combination of radiation. Results: This approach demonstrated that the tested compounds at the concentrations utilized have little or no cytotoxicity towards the radioresistant HT29 cell line but have great cytotoxicity and radiosensitizer activity when combined with irradiation. Conclusion: The novel bifunctional unsaturated conjugated aryl ketones which are thiol alkylators found to exhibit radiosensitivity activity. Consequently, these new developed compounds should be evaluated further to assess their potential efficacy with radiotherapy to combat malignancies in a pre-clinical animal model. [ABSTRACT FROM AUTHOR]