Background And Purpose: In proton therapy, a relative biological effectiveness (RBE) of 1.1 is used toreach an isoeffective biological response between photon and proton doses. However, the RBE varies with biological endpoints and linear energy transfer (LET), two key parameters in radiotherapy.
View Article and Find Full Text PDFThis study presents a novel approach to skin toxicity assessment in preclinical radiotherapy trials through an advanced imaging setup and deep learning. Skin reactions, commonly associated with undesirable side effects in radiotherapy, were meticulously evaluated in 160 mice across four studies. A comprehensive dataset containing 7542 images was derived from proton/electron trials with matched manual scoring of the acute toxicity on the right hind leg, which was the target area irradiated in the trials.
View Article and Find Full Text PDFContext: Functional imaging with positron emission tomography (PET) scans is an essential part of the diagnostic workup for pheochromocytoma and paraganglioma (PPGL). The purpose of this review is to (1) provide a brief overview of functional imaging for PPGL, (2) summarize selected present and older guideline and review recommendations, and (3) conduct a literature review on the diagnostic performance of the most used PET tracers for PPGL.
Evidence Acquisition: We conducted a systematic literature search in PubMed from January 2004 to August 2024 with the search string ("Pheochromocytoma" OR "Paraganglioma") AND ("Positron Emission Tomography" OR "Radionuclide Imaging" OR ("PET" AND ("FDG" OR "DOTATOC" OR "DOTANOC" OR "DOTATATE" OR "DOPA" OR "FDOPA"))).
Background: Patients with locally advanced prostate cancer require the prostate and pelvic lymph nodes to be irradiated simultaneously during radiation therapy treatment. However, relative motion between treatment targets decreases dosimetric conformity. Current treatment methods mitigate this error by having large treatment margins and often prioritize the prostate at patient setup at the cost of lymph node coverage.
View Article and Find Full Text PDFBackground: Radiotherapy of the prostate and the pelvic lymph nodes (LN) is a part of the standard of care treatment for high-risk prostate cancer. The independent translational and rotational (i.e.
View Article and Find Full Text PDFBackground And Purpose: Oxygen dynamics may be important for the tissue-sparing effect observed at ultra-high dose rates (FLASH sparing effect). This study investigated the correlation between local instantaneous dose rate and radiation-induced oxygen pressure reduction during proton pencil beam scanning (PBS) irradiations of a sample and quantified the oxygen consumption g-value.
Materials And Methods: A 0.
Contact Dermatitis
December 2024
Background: Formaldehyde is a common cause of contact allergy. Hidden formaldehyde, that is, formaldehyde in products without formaldehyde releasers, has previously been detected in cosmetic products.
Objectives: The objective of this study was to investigate the content and causes of hidden formaldehyde in leave-on cosmetic products.
Background And Purpose: The impact of intrafractional motion and deformations on clinical radiotherapy delivery has so far only been investigated by simulations as well as point and planar dose measurements. The aim of this study was to combine anthropomorphic 3D dosimetry with a deformable abdominal phantom to measure the influence of intra-fractional motion and gating in photon radiotherapy and evaluate the applicability in proton therapy.
Material And Methods: An abdominal phantom was modified to hold a deformable anthropomorphic 3D dosimeter shaped as a human liver.
This study aims to investigate the continuum of glucose control from normoglycemia to dysglycemia (HbA1c ≥ 5.7%/39 mmol/mol) using metrics derived from continuous glucose monitoring (CGM). In addition, we aim to develop a machine learning-based classification model to classify dysglycemia based on observed patterns.
View Article and Find Full Text PDFAims/hypothesis: The apparent diffusion coefficient (ADC) derived from diffusion-weighted MRI (DWI-MRI) has been proposed as a measure of changes in kidney microstructure, including kidney fibrosis. In advanced kidney disease, the kidneys often become atrophic; however, in the initial phase of type 2 diabetes, there is an increase in renal size. Glucagon-like peptide-1 receptor agonists and sodium-glucose cotransporter 2 inhibitors both provide protection against progression of kidney disease in diabetes.
View Article and Find Full Text PDFObjective: A favorable effect of ultra-high dose rate (FLASH) radiation on normal tissue-sparing has been indicated in several preclinical studies. In these studies, the adverse effects of radiation damage were reduced without compromising tumor control. Most studies of proton FLASH investigate these effects within the entrance of a proton beam.
View Article and Find Full Text PDFInt J Radiat Oncol Biol Phys
September 2024
Purpose: Preclinical studies have shown a preferential normal tissue sparing effect of FLASH radiation therapy with ultra-high dose rates. The aim of the present study was to use a murine model of acute skin toxicity to investigate the biologic effect of varying dose rates, time structure, and introducing pauses in the dose delivery.
Methods And Materials: The right hind limbs of nonanaesthetized mice were irradiated in the entrance plateau of a pencil beam scanning proton beam with 39.
Introduction: Pheochromocytomas and paragangliomas are rare neuroendocrine tumours that originate from chromaffin cells within the adrenal medulla or extra-adrenal sympathetic ganglia. Management of disseminated or metastatic pheochromocytomas and paragangliomas continues to pose challenges and relies on limited evidence.
Method: In this study, we report retrospective data on median overall survival (OS) and median progression-free survival (PFS) for all Danish patients treated with peptide receptor radionuclide therapy (PRRT) with Lu-Dotatate or Y-Dotatate over the past 15 years.
Background: Dosimetry in pre-clinical FLASH studies is essential for understanding the beam delivery conditions that trigger the FLASH effect. Resolving the spatial and temporal characteristics of proton pencil beam scanning (PBS) irradiations with ultra-high dose rates (UHDR) requires a detector with high spatial and temporal resolution.
Purpose: To implement a novel camera-based system for time-resolved two-dimensional (2D) monitoring and apply it in vivo during pre-clinical proton PBS mouse irradiations.
Purpose: The aim of this work was to investigate the ability of a biological oxygen enhancement ratio-weighted dose, D, to describe acute skin toxicity variations observed in mice after proton pencil beam scanning irradiations with changing doses and beam time structures.
Methods And Materials: In five independent experiments, the right hind leg of a total of 621 CDF1 mice was irradiated previously in the entrance plateau of a pencil beam scanning proton beam. The incidence of acute skin toxicity (of level 1.
Background: Radiobiological experimental setups are challenged by precise sample positioning along depth dose profile, scattering conditions, and practical difficulties that must be addressed in individual designs. The aim of this study was to produce cell survival curves with several irradiation modalities, by using a setup designed at the Danish Centre for Particle Therapy (DCPT) for in vitro proton irradiations using a horizontal beam line and thereby evaluating the setups use for in vitro irradiations experiments.
Materials And Methods: The setup is a water phantom suitable for in vitro research with multiple irradiation modalities, in particular the pencil scanning proton beam available from a horizontal experimental beamline.
Introduction: Central aortic blood pressure (BP) could be a better risk predictor than brachial BP. This study examined whether invasively measured aortic systolic BP improved outcome prediction beyond risk prediction by conventional cuff-based office systolic BP in patients with and without chronic kidney disease (CKD).
Methods: In a prospective, longitudinal cohort study, aortic and office systolic BPs were registered in patients undergoing elective coronary angiography (CAG).
The objective of this study was to assess the feasibility of the Arteriograph 24 device to measure 24-hour PWV and central systolic blood pressure (cSBP) in patients with type 2 diabetes (T2DM) and non-diabetic controls and compare daytime and nighttime characteristics in the two groups. Twenty-four-hour PWV and cSBP was measured in 58 patients with T2DM (mean age: 66 ± 9 years, 50% women, mean duration of T2DM: 7.8 ± 1.
View Article and Find Full Text PDFAim: Despite the increasing use of combination treatment with sodium-glucose cotransporter 2 inhibitors and glucagon-like peptide-1 receptor agonists, data are limited on the effects of combination treatment on markers of cardiovascular disease. This study aimed to investigate the effect of empagliflozin, semaglutide, and their combination on vascular function.
Materials And Methods: In total, 120 patients with type 2 diabetes were randomized into four groups (n = 30 in each) for 32 weeks: placebo, semaglutide, empagliflozin, and their combination.
Aims: To evaluate the effect of treatment with semaglutide and empagliflozin on the cortico-medullary sodium gradient (MCR; medulla/cortex ratio), urine sodium/creatinine ratio (UNACR), and estimated plasma volume (ePV) and to compare the MCR between persons with and without type 2 diabetes.
Methods: Using the Na magnetic resonance imaging (Na-MRI) technique, we investigated the effects of 32 weeks of treatment with semaglutide, empagliflozin or their combination on MCR in 65 participants with type 2 diabetes and high risk of cardiovascular disease. The participants were recruited from a randomized, controlled interventional trial and further characterized by UNACR and ePV.
Background: Duchenne Muscular Dystrophy (DMD) is a progressive genetic disease with a prevalence of 1 per 3,600-6,000 male births. Individuals with DMD are typically diagnosed at age 4-7 years; median survival is 30 years. They require multidisciplinary care, personal assistance, and often special education.
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