Quantification of the dependencies of the Bragg peak degradation due to lung tissue in proton therapy on a CT-based lung tumor phantom.

The fine, sub-millimeter sized structure of lung tissue causes a degradation of the Bragg peak curve in particle therapy. The Bragg peak is degraded because particles of the same energy traverse lung tissue of different compositions of high and low density materials. Hence, they experience different energy losses resulting in variable ranges and a broadened Bragg peak.

Fluence-weighted average subfield size in helical TomoTherapy.

Introduction: Helical TomoTherapy allows a highly conformal dose distribution to complex target geometries with a good protection of organs at risk. However, the small field sizes associated with this method are a possible source of dosimetrical uncertainties. The IAEA has published detector-specific field output correction factors for static fields of the TomoTherapy in the TRS483.

IL-10 signaling in dendritic cells is required for tolerance induction in a murine model of allergic airway inflammation.

Allergen specific tolerance induction efficiently ameliorates subsequent allergen induced inflammatory responses. The underlying regulatory mechanisms have been attributed mainly to interleukin (IL)-10 produced by diverse hematopoietic cells, while targets of IL-10 in allergen specific tolerance induction have not yet been well defined. Here, we investigate potential cellular targets of IL-10 in allergen specific tolerance induction using mice with a cell type specific inactivation of the IL-10 receptor gene.

Decomposition of the dose conversion factor based on fluence spectra of secondary charged particles: Application to lateral dose profiles in photon fields.

Purpose: The dose conversion factor plays an important role in the dosimetry by enabling the absorbed dose in the sensitive volume of a detector to be converted into the absorbed dose in the surrounding medium (in most cases water). The purpose of this paper is to demonstrate that a specific fluence-based approach for the decomposition of the dose conversion factor is in particular useful for the interpretation of the influences of detector properties on measurements under nonreference conditions.

Methods: Data for the dose conversion factor and secondary fluence spectra were obtained by the Monte Carlo method.

Characterization of the honeybee venom proteins C1q-like protein and PVF1 and their allergenic potential.

Honeybee (Apis mellifera) venom (HBV) represents an ideal model to study the role of particular venom components in allergic reactions in sensitized individuals as well as in the eusociality of Hymenoptera species. The aim of this study was to further characterize the HBV components C1q-like protein (C1q) and PDGF/VEGF-like factor 1 (PVF1). C1q and PVF1 were produced as recombinant proteins in insect cells.

Experimental and Monte Carlo-based determination of the beam quality specifier for TomoTherapyHD treatment units.

Reference dosimetry by means of clinical linear accelerators in high-energy photon fields requires the determination of the beam quality specifier TPR, which characterizes the relative particle flux density of the photon beam. The measurement of TPR has to be performed in homogenous photon beams of size 10×10cm with a focus-detector distance of 100cm. These requirements cannot be fulfilled by TomoTherapy treatment units from Accuray.

An efficient method to predict and include Bragg curve degradation due to lung-equivalent materials in Monte Carlo codes by applying a density modulation.

Sub-millimetre-sized heterogeneities such as lung parenchyma cause Bragg peak degradation which can lead to an underdose of the tumor and an overdose of healthy tissue when not accounted for in treatment planning. Since commonly used treatment-planning CTs do not resolve the fine structure of lungs, this degradation can hardly be considered. We present a mathematical model capable of predicting and describing Bragg peak degradation due to a lung-equivalent geometry consisting of sub-millimetre voxels filled with either lung tissue or air.

Predominant Api m 10 sensitization as risk factor for treatment failure in honey bee venom immunotherapy.

Background: Component resolution recently identified distinct sensitization profiles in honey bee venom (HBV) allergy, some of which were dominated by specific IgE to Api m 3 and/or Api m 10, which have been reported to be underrepresented in therapeutic HBV preparations.

Objective: We performed a retrospective analysis of component-resolved sensitization profiles in HBV-allergic patients and association with treatment outcome.

Methods: HBV-allergic patients who had undergone controlled honey bee sting challenge after at least 6 months of HBV immunotherapy (n = 115) were included and classified as responder (n = 79) or treatment failure (n = 36) on the basis of absence or presence of systemic allergic reactions upon sting challenge.

Scanned ion beam therapy for prostate carcinoma: Comparison of single plan treatment and daily plan-adapted treatment.

Background And Purpose: Intensity-modulated particle therapy (IMPT) for tumors showing interfraction motion is a topic of current research. The purpose of this work is to compare three treatment strategies for IMPT to determine potential advantages and disadvantages of ion prostate cancer therapy.

Materials And Methods: Simulations for three treatment strategies, conventional one-plan radiotherapy (ConvRT), image-guided radiotherapy (IGRT), and online adaptive radiotherapy (ART) were performed employing a dataset of 10 prostate cancer patients with six CT scans taken at one week intervals.

The influence of neutron contamination on dosimetry in external photon beam radiotherapy.

Purpose: Photon fields with energies above ∼7 MeV are contaminated by neutrons due to photonuclear reactions. Their influence on dosimetry-although considered to be very low-is widely unexplored.

Methods: In this work, Monte Carlo based investigations into this issue performed with fluka and egsnrc are presented.

Presurgical orthopedics by drink plates does not significantly normalize deglutition in infants with cleft lip and palate.

Objective: To test the null hypothesis of no significant difference between intraoral pressure characteristics in infants with cleft lip and palate (CLP) with or without presurgical orthopedic (PSO) plates (groups CLP and CLP-PSO), compared with noncleft infants.

Materials And Methods: Intraoral atmospheric pressure assessments were performed on 17 subjects with preoperative CLP (m/f, 11/6; mean/SD, 4.76/0.

Monte Carlo study of the depth-dependent fluence perturbation in parallel-plate ionization chambers in electron beams.

Purpose: The electron fluence inside a parallel-plate ionization chamber positioned in a water phantom and exposed to a clinical electron beam deviates from the unperturbed fluence in water in absence of the chamber. One reason for the fluence perturbation is the well-known "inscattering effect," whose physical cause is the lack of electron scattering in the gas-filled cavity. Correction factors determined to correct for this effect have long been recommended.