Unlabelled: The effectiveness of radiotherapy treatment is influenced by the position of beam focal spot; therefore, it is important to verify the beam focal spot periodically. In this study the beam focal spot offset is measured using an electronic portal imaging (EPID) based technique and co- rotational penumbra modulation technique(CPM).
Materials And Methods: This method utilizes one set of jaws and the multileaf collimator (MLC) to form a symmetric field and then a 180o collimator rotation was utilized to determine the radiation isocenter defined by the jaws and the MLC, respectively. The difference between these two isocentres is then directly correlated with the beam focal spot offset of the linear accelerator. In the current study, the method has been used for Varian ClinaciX and Elekta Versa HD linear accelerators. Since an Elektalinac with the Agility® head does not have two set of jaws, a modified method that making use of one set of diaphragms, the MLC and a full 360o collimator rotation is implemented.
Result: The method is validated against CPM and found to be in agreement within 0.00923± 0.009360 mm ( SD) also the method has been found to be reproducible to within 0.0365 mm (SD).
Conclusion: The method could be used for routine quality assurance (QA) to ensure that the beam focal spot offset is in tolerance.
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BMC Cancer
January 2025
Taras Shevchenko National University of Kyiv, 64/13, Volodymyrska Street, Kyiv, 01601, Ukraine.
Background: nowadays, the photoacoustic imaging is in the mainstream of cancer theranostics. In this study the nanoparticles with previously proven photoacoustic imaging properties, i.e.
View Article and Find Full Text PDFFront Immunol
January 2025
Department of Dermatology, Northwestern University, Feinberg School of Medicine, Chicago, IL, United States.
Introduction: Cutaneous T-cell lymphoma (CTCL) is closely associated with the host microbiome. While recent evidence suggests that shifts in specific bacterial taxa are associated with response to UV-B, a form of non-ionizing radiation, the impact of ionizing radiation (IR) has not been investigated.
Methods: 16S rRNA and gene amplicon sequencing were performed on DNA extracted from swabs of lesional/non-lesional skin of 12 CTCL patients before/after TSEBT or local IR and from 25 matched healthy controls (HC).
J Cell Biol
March 2025
Department of Biology, Massachusetts Institute of Technology, Cambridge, MA, USA.
Upon invasion into the host cell, a subset of bacterial pathogens resides exclusively in the cytosol. While previous research revealed how they reshape the plasma membrane during invasion, subvert the immune response, and hijack cytoskeletal dynamics to promote their motility, it was unclear if these pathogens also interacted with the organelles in this crowded intracellular space. Here, we examined if the obligate intracellular pathogen Rickettsia parkeri interacts with the endoplasmic reticulum (ER), a large and dynamic organelle spread throughout the cell.
View Article and Find Full Text PDFEur J Endocrinol
January 2025
Department of Pediatric Oncology, Princess Máxima Center for Pediatric Oncology, 3584 CS Utrecht, The Netherlands.
Objective: Survivors of pediatric head and neck rhabdomyosarcoma (HNRMS) are at risk of developing endocrinopathies following local treatment, resulting from radiation damage to the pituitary gland, hypothalamus, or thyroid gland, often at a young age. Our aim was to determine the prevalence of endocrine dysfunction in long-term HNRMS survivors and compare the prevalence of anterior pituitary insufficiency (API) among different local treatment strategies: external beam radiation with photons, external beam radiation with protons, microscopically radical surgery combined with external irradiation, and macroscopic radical surgery combined with brachytherapy.
Design And Methods: Head and neck rhabdomyosarcoma survivors treated between 1993 and 2017, with ≥2 years of follow-up, without recurrent disease or secondary malignancy were eligible for this study.
Oper Neurosurg (Hagerstown)
January 2025
Department of Neurosurgery, Yeditepe University School of Medicine, İstanbul, Türkiye.
Background And Objectives: The middle fossa approaches are tremendously versatile for treating small vestibular schwannomas, selected petroclival meningiomas, midbasilar trunk aneurysms, and lesions of the petrous bone. Our aim was to localize the internal acoustic canal and safely drill the petrous apex with these approaches. This study demonstrates a new method to locate the internal acoustic canal during surgery in the middle fossa.
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