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Cell death is one of the inevitable life activities of cells during the growth and development of the body. Regulated cell death (RCD) is a type of cell death mode that can be regulated and depends on specific molecular mechanisms which play an essential role in various pathophysiological environments. Pyrolysis is a newly discovered method of programmed cell death mediated by members of the Gasdermin protein family which is characterized by the activation of inflammatory factors and the formation of cell membrane pores. The specific manifestations are the swelling of cells, the appearance of plasma membrane bullae and the release of cell contents after cell rupture. A cascade of inflammation occurs after cell death. Activation of inflammasomes activates the classic pyrolysis pathway depending on caspase-1 or the non-classical pyrolysis pathway depending on Caspase-4/5/11 and the subsequent inflammation reaction, excessive immune response caused by microbial infection and danger signals can lead to a variety of inflammatory diseases. In the inflammatory response, large numbers of inflammasomes activate the substrate protein GSDMD. GSDMD mediates pyrolysis by forming pores in the plasma membrane and mitochondria. Many studies have shown that pyrolysis plays an essential role in inflammatory bowel disease and other inflammatory diseases. This article aims to elaborate on the molecular mechanisms of pyroptosis in ulcerative colitis (UC) pathogenesis and provide new therapeutic ideas for UC. [ABSTRACT FROM AUTHOR]

The correct equation should be 2 HT ht where ( I W i / I e i ) SB air sb is the average energy expended per unit charge of ionization produced in dry air, having the value 33.97 J/C, and (1 - I g i ) corrects for the effect of radiative losses (mainly due to bremsstrahlung emission) by the secondary charged particles, and I g i is less than 0.1% for photons below 300 keV in air. Erratum: "AAPM protocol for 40-300 kV x-ray beam dosimetry in radiotherapy and radiobiology". [Extracted from the article]

Purpose: High dose rate brachytherapy (HDR-BT) has been shown to be an effective treatment for prostate cancer, with treatment plan quality dependent on a number of factors. In this work, we report on the overall performance of our ultrasound (US)-based workflow and the impact of several treatment-specific variables., Methods and Materials: Patients who underwent HDR-BT (boost, monotherapy, and retreatment) using Varian Bravos/US from 2021 to 2023 were sampled for this study. Treatment plan quality was analyzed and plans were categorized with regard to a number of metrics, including: prostate volume, treating physician, planning physicist, number of needles included, estimated planning time, rectum-prostate separation, and bladder-prostate separation. The performance of this program was compared to the performance of our program using previously used modality combinations: Varian Varisource/US, Elekta microSelectron/CT., Results: Plan quality for our Bravos/US workflow was shown to be consistently above acceptability criteria for all personnel involved; on average: prostate V100%: 98.9% ± 0.1%, rectum V75%: 0.04 ± 0.01 cc, bladder V75%: 0.06 ± 0.01cc, urethra V125%: 0.00 ± 0.00 cc. Prostate coverage was statistically improved with this workflow compared to that using our previous modalities. There was a statistical correlation between organ-at-risk sparing/prostate coverage ratio and prostate volume, number of needles/prostate volume, bladder-prostate separation, and rectum-prostate separation. There was no correlation between plan quality and planning time., Conclusions: Our US-based HDR-BT program led to target coverage and organ-at-risk sparing that exceeded department thresholds. Results were acceptable regardless of the personnel involved and improved plan quality was obtained using more needles/prostate volume and increased spacing between the prostate and the rectum and bladder., (Copyright © 2024 American Brachytherapy Society. Published by Elsevier Inc. All rights reserved.)

In imaged-guided radiation therapy (IGRT), target localization is usually done with rigid-body registration based on anatomy matching. Problems arise when the target volume can only be matched partially due to inter-fractional organ motion and deformation, resulting in deteriorated target coverage and critical structure sparing. A new target localization method is investigated in which the treatment target volume is aligned with the prescription isodose surface. Our study included 15 prostate patients previously treated with intensity-modulated radiation therapy (IMRT). Patient setup and target localization were performed using a CT-on-rails system before and after the IMRT treatment. IMRT plans were generated on the original simulation CTs (15) and the same MUs and leaf sequences were used to compute the dose distributions on post-treatment CTs (98) with the isocenter adjustments based on either anatomical structure matching or prescription isodose surface alignment. When patients were aligned with the traditional anatomy matching method, the dose to 95% of the CTV, D 95 , received 74.0 - 77.6 Gy and the minimum CTV dose, D min , was 61.9 - 71.6 Gy, respectively, in the cumulative dose distributions. The rectal dose-volume constraints were violated in 35.7% of the treatment fractions. When patients were aligned using the new localization method, the dose to 95% of the CTV, D 95 , received 74.0 - 78.2 Gy and the minimum CTV dose, D min , was 68.4 - 71.6 Gy, respectively, in the cumulative dose distributions. The rectal dose-volume constraints were violated in 17.3% of the treatment fractions. Traditional IGRT target localization based on anatomy matching is effective for population-based PTV margins but not ideal for those patients with large inter-fractional prostate rotation/deformation due to large rectal and bladder volume variation. The new method using the prescription isodose surface to align the target volume could improve the target coverage and rectal sparing for these patients, which can be implemented clinically to improve target dose delivery accuracy., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Associazione Italiana di Fisica Medica e Sanitaria. Published by Elsevier Ltd. All rights reserved.)