The proton RBE and the distal edge effect for acute and late normal tissue damage in vivo.

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.

Danish and Swedish National Data Collections for Cancer - Solutions for Radiotherapy.

Collecting large amounts of radiotherapy (RT) data from clinical systems is known to be a challenging task. Still, data collections outside the original RT systems are needed to follow-up on the quality of cancer care and to improve RT. This paper aims to describe how RT data is collected nationally in Denmark and Sweden for this purpose and gives an overview of the stored information in both countries' national data sources.

[A practical model to implement the patient participation in tertiary hospitals (ICE model)].

Objective: Democratise healthcare and research through a model that ensures the participation of patients and professionals.

Method: Weaknesses are analysed and corrections are articulated with a model through biweekly meetings between the hospital's citizen attention and healthcare management.

Results: The resulting model is proactive in nature, deployed between November-2021 and December-2023 and had three elements: Information, Co-creation and Strategy (ICE).

Water-Based Polyurethane Dispersions: A Detailed Analysis of the Particle Charge Using Soft and Hard Particle Model.

Water-based polyurethane dispersions (PUDs) show a characteristic dependency of the electrophoretic mobility on the electrolyte concentration, which can be investigated by hard and soft particle models. For this purpose, additional information can be obtained by determining particle charges and electrostatic potentials. PUDs with different contents of an intrinsic ionic stabilizer and various polyol components were synthesized according to the acetone process.

Acute toxicities in proton therapy for head and neck cancer - A matched analysis of the DAHANCA 35 feasibility study.

Background And Purpose: As preparation for a national randomized study comparing proton radiotherapy to photon radiotherapy, DAHANCA 35, we performed a non-randomized pilot study to investigate patient selection, logistics, planning, and treatment delivery. With the present study, as a comprehensive safety analysis, we want to compare toxicity during and up to two months after therapy to a historically matched group of patients treated with photon radiotherapy.

Materials And Methods: 62 patients treated with protons were matched to 124 patients who received photon treatment outside a protocol.

Correlation between local instantaneous dose rate and oxygen pressure reduction during proton pencil beam scanning irradiation.

Background 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.

Physician barriers and dilemmas in the execution of clinical trials impacting decision-making in the DAHANCA 35 proton therapy trial for head and neck cancer.

Background: Physicians manage multiple obligations, providing best-practice treatment and patient- centred care in the standard treatment pathway while contributing to clinical trials simultaneously. These multifaceted responsibilities may introduce barriers and dilemmas to clinical trial execution, potentially impacting the clinical trial decision- making process. This study explores physicians' barriers and dilemmas in executing clinical trials and the impact on clinical trial decision-making.

Spread-out Bragg peak FLASH: quantifying normal tissue toxicity in a murine model.

Objective: 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.

Assessing the reduction of viral infectivity in HPV16/18-positive women after one, two, and three doses of Gardasil-9 (RIFT): Study protocol.

Human Papillomavirus (HPV) prophylactic vaccination has proven effective in preventing new infections, but it does not treat existing HPV infections or associated diseases. Hence, there is still an important reservoir of HPV in adults, as vaccination programs are mainly focused on young women. The primary objective of this non-randomized, open-label trial is to evaluate if a 3-dose regimen of Gardasil-9 in HPV16/18-positive women could reduce the infective capacity of their body fluids.

Proton FLASH: Impact of Dose Rate and Split Dose on Acute Skin Toxicity in a Murine Model.

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.

Towards a European prospective data registry for particle therapy.

The evidence for the value of particle therapy (PT) is still sparse. While randomized trials remain a cornerstone for robust comparisons with photon-based radiotherapy, data registries collecting real-world data can play a crucial role in building evidence for new developments. This Perspective describes how the European Particle Therapy Network (EPTN) is actively working on establishing a prospective data registry encompassing all patients undergoing PT in European centers.

Comparison of 3-year local control using DAHANCA radiotherapy guidelines before and after implementation of five millimetres geometrical GTV to high-dose CTV margin.

Introduction: Treatment planning using a five-millimetre geometrical margin from GTV to high-dose CTV (CTV1) has been used in DAHANCA treatment centres since 2013. We aimed to evaluate changes in CTV1 volumes, local control (LC), and recurrence pattern after the implementation of five-millimetre geometrical margins nationally.

Materials And Methods: 1,948 patients with pharyngeal, and laryngeal squamous cell carcinomas completed definitive IMRT-based treatment in 2010-2012 and 2013-2015 in three centres.

Oxygen Enhancement Ratio-Weighted Dose Quantitatively Describes Acute Skin Toxicity Variations in Mice After Pencil Beam Scanning Proton FLASH Irradiation With Changing Doses and Time Structures.

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.

Investigation of the Electrokinetic Properties of HIV-Based Virus-Like Particles.

The antigen density on the surface of HIV-based virus-like particles (VLPs) plays a crucial role in the improvement of HIV vaccine potency. HIV VLPs consist of a dense protein core, which is surrounded by a lipid bilayer and whose surface is usually decorated with antigenic glycoproteins. The successful downstream processing of these particles is challenging, and the high-resolution and cost-efficient purification of HIV-based VLPs has not yet been achieved.

Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023.

Central Illustration : Position Statement on the Use of Myocardial Strain in Cardiology Routines by the Brazilian Society of Cardiology's Department Of Cardiovascular Imaging - 2023 Proposal for including strain in the integrated diastolic function assessment algorithm, adapted from Nagueh et al.67 Am: mitral A-wave duration; Ap: reverse pulmonary A-wave duration; DD: diastolic dysfunction; LA: left atrium; LASr: LA strain reserve; LVGLS: left ventricular global longitudinal strain; TI: tricuspid insufficiency. Confirm concentric remodeling with LVGLS.

Exploring patient-reported barriers to participating in proton therapy clinical trials.

Introduction: Clinical trials lead the progress in healthcare. To ensure reliable research conclusions, it is essential to enroll diverse patient groups. Identifying and understanding patient-reported barriers to clinical trials may help enhance recruitment among diverse patient groups.

Mitochondrial modulation with leriglitazone as a potential treatment for Rett syndrome.

Background: Rett syndrome is a neuropediatric disease occurring due to mutations in MECP2 and characterized by a regression in the neuronal development following a normal postnatal growth, which results in the loss of acquired capabilities such as speech or purposeful usage of hands. While altered neurotransmission and brain development are the center of its pathophysiology, alterations in mitochondrial performance have been previously outlined, shaping it as an attractive target for the disease treatment.

Methods: We have thoroughly described mitochondrial performance in two Rett models, patients' primary fibroblasts and female Mecp2 mice brain, discriminating between different brain areas.

Considerations for study design in the DAHANCA 35 trial of protons versus photons for head and neck cancer.

Proton radiotherapy offers a dosimetric advantage compared to photon therapy in sparing normal tissue, but the clinical evidence for toxicity reductions in the treatment of head and neck cancer is limited. The Danish Head and Neck Cancer Group (DAHANCA) has initiated the DAHANCA 35 randomised trial to clarify the value of proton therapy (NCT04607694). The DAHANCA 35 trial is performed in an enriched population of patients selected by an anticipated benefit of proton therapy to reduce the risk of late dysphagia or xerostomia based on normal tissue complication probability (NTCP) modelling.

A national repository of complete radiotherapy plans: design, Results, and experiences.

Background: Previously, many radiotherapy (RT) trials were based on a few selected dose measures. Many research questions, however, rely on access to the complete dose information. To support such access, a national RT plan database was created.

Consistency in contouring of organs at risk by artificial intelligence vs oncologists in head and neck cancer patients.

Background: In the Danish Head and Neck Cancer Group (DAHANCA) 35 trial, patients are selected for proton treatment based on simulated reductions of Normal Tissue Complication Probability (NTCP) for proton compared to photon treatment at the referring departments. After inclusion in the trial, immobilization, scanning, contouring and planning are repeated at the national proton centre. The new contours could result in reduced expected NTCP gain of the proton plan, resulting in a loss of validity in the selection process.