Recommendations for using analytical anisotropic algorithm and AcurosXB for epidermal dose calculations in breast radiotherapy from an in vivo Gafchromic film study.

Background And Purpose: This study recommends clinical epidermal dose calculation methods based on in-vivo film measurements and registered skin dose distributions with the Eclipse (Varian Medical Systems) treatment planning system's Analytical Anisotropic Algorithm (AAA) and Acuros XB (AXB) dose calculation algorithms.

Materials And Methods: Eighteen AAA V13.6 breast plans were recalculated using AXB (dose to medium) V13.

Toward a Skin Dose-Area Metric Predictive of Moist Desquamation Using In Vivo Skin Dosimetry and Skin Assessments.

Purpose: Moist desquamation (MD) is a concerning acute side effect of radiation therapy for breast cancer, often seen in skin folds for patients having large or pendulous breasts. In vivo skin dosimetry, clinical assessments, and patient-reported skin reactions were used to determine a relationship between dose-area metrics and the development of MD, to lend insight into skin tolerances and possibly guide future treatment planning dose constraints.

Methods And Materials: Skin dose was measured using GafChromic film on the inner surface of an early prototype carbon-fiber accessory for breast support to remove the inframammary fold in 20 patients at high risk of developing MD undergoing adjuvant whole breast radiation therapy.

Four-dimensional treatment planning strategies for dynamic tumor tracking.

Introduction: Dynamic tumor tracking (DTT) is a motion management technique where the radiation beam follows a moving tumor in real time. Not modelling DTT beam motion in the treatment planning system leaves an organ at risk (OAR) vulnerable to exceeding its dose limit. This work investigates two planning strategies for DTT plans, the "Boolean OAR Method" and the "Aperture Sorting Method," to determine if they can successfully spare an OAR while maintaining sufficient target coverage.

Monte Carlo Modeling of Dynamic Tumor Tracking on a Gimbaled Linear Accelerator.

Purpose And Aim: The Vero4DRT (Brainlab AG) linear accelerator is capable of dynamic tumor tracking (DTT) by panning/tilting the radiation beam to follow respiratory-induced tumor motion in real time. In this study, the panning/tilting motion is modeled in Monte Carlo (MC) for quality assurance (QA) of four-dimensional (4D) dose distributions created within the treatment planning system (TPS).

Materials And Methods: Step-and-shoot intensity-modulated radiation therapy plans were optimized for 10 previously treated liver patients.

Impact of Inflammation on Midazolam Metabolism in Severe COVID-19 Patients.

Midazolam is a benzodiazepine frequently used for sedation in patients hospitalized in the intensive care unit (ICU) for coronavirus disease 2019 (COVID-19). This drug is primarily metabolized by cytochrome P450 3A (CYP3A) isoenzymes. Several studies have suggested that inflammation, frequently observed in these patients, could modulate CYP3A activity.

A metamodel-based flexible insulin therapy for type 1 diabetes patients subjected to aerobic physical activity.

Patients with type 1 diabetes are subject to exogenous insulin injections, whether manually or through (semi)automated insulin pumps. Basic knowledge of the patient's characteristics and flexible insulin therapy (FIT) parameters are then needed. Specifically, artificial pancreas-like closed-loop insulin delivery systems are some of the most promising devices for substituting for endogenous insulin secretion in type 1 diabetes patients.

SELENOT Deficiency in the Mouse Brain Impacts Catecholaminergic Neuron Density: An Immunohistochemical, in situ Hybridization and 3D Light-Sheet Imaging Study.

Background: Selenoprotein T (SELENOT), a PACAP-regulated thioredoxin-like protein, plays a role in catecholamine secretion and protects dopaminergic neurons. However, the role of SELENOT in the establishment of the catecholaminergic (CA) neuronal system is not known yet.

Methods: We analyzed by immunohistochemistry and RNAscope in situ hybridization the distribution of SELENOT and the expression of its mRNA, respectively.

Highly Accurate Real-Time Decomposition of Single Channel Intramuscular EMG.

Objective: Real-time intramuscular electromyography (iEMG) decomposition, as an identification procedure of individual motor neuron (MN) discharge timings from a streaming iEMG recording, has the potential to be used in human-machine interfacing. However, for these applications, the decomposition accuracy and speed of current approaches need to be improved.

Methods: In our previous work, a real-time decomposition algorithm based on a Hidden Markov Model of EMG, using GPU-implemented Bayesian filter to estimate the spike trains of motor units (MU) and their action potentials (MUAPs), was proposed.

Reduction in Doses to Organs at Risk and Normal Tissue During Breast Radiation Therapy With a Carbon-Fiber Adjustable Reusable Accessory.

Purpose: This pilot study (ClinicalTrials.gov NCT04543851) investigates a novel breast positioning device using a low density, high tensile carbon-fiber cradle to support the breast, remove the inframammary fold, and reduce dose to organs at risk for whole breast radiation therapy in the supine position.

Methods And Materials: Thirty patients with inframammary folds ≥1 cm or lateral ptosis in supine treatment position were planned with standard positioning and with a carbon-fiber Adjustable Reusable Accessory (CARA) breast support.

Four-dimensional dose calculations for dynamic tumour tracking with a gimbal-mounted linear accelerator.

Purpose: In this study we present a novel method for re-calculating a treatment plan on different respiratory phases by accurately modeling the panning and tilting beam motion during DTT (the "rotation method"). This method is used to re-calculate the dose distribution of a plan on multiple breathing phases to accurately assess the dosimetry.

Methods: sIMRT plans were optimized on a breath hold computed tomography (CT) image taken at exhale (BH ) for 10 previous liver stereotactic ablative radiotherapy patients.

Simulation of Motor Unit Action Potential Recordings From Intramuscular Multichannel Scanning Electrodes.

Unlabelled: Multi-channel intramuscular EMG (iEMG) provides information on motor neuron behavior, muscle fiber (MF) innervation geometry and, recently, has been proposed as a means to establish a human-machine interface.

Objective: to provide a reliable benchmark for computational methods applied to such recordings, we propose a simulation model for iEMG signals acquired by intramuscular multi-channel electrodes.

Methods: we propose several modifications to the existing motor unit action potentials (MUAPs) simulation methods, such as farthest point sampling (FPS) for the distribution of motor unit territory centers in the muscle cross-section, accurate fiber-neuron assignment algorithm, modeling of motor neuron action potential propagation delay, and a model of multi-channel scanning electrode.

On-Line Recursive Decomposition of Intramuscular EMG Signals Using GPU-Implemented Bayesian Filtering.

Objective: Real-time intramuscular electromyography (iEMG) decomposition, which is needed in biofeedback studies and interfacing applications, is a complex procedure that involves identifying the motor neuron spike trains from a streaming iEMG recording.

Methods: We have previously proposed a sequential decomposition algorithm based on a Hidden Markov Model of EMG, which used Bayesian filter to estimate unknown parameters of motor unit (MU) spike trains, as well as their action potentials (MUAPs). Here, we present a modification of this original model in order to achieve a real-time performance of the algorithm as well as a parallel computation implementation of the algorithm on Graphics Processing Unit (GPU).

Individuals have unique muscle activation signatures as revealed during gait and pedaling.

Although it is known that the muscle activation patterns used to produce even simple movements can vary between individuals, these differences have not been considered to prove the existence of individual muscle activation strategies (or signatures). We used a machine learning approach (support vector machine) to test the hypothesis that each individual has unique muscle activation signatures. Eighty participants performed a series of pedaling and gait tasks, and 53 of these participants performed a second experimental session on a subsequent day.

Impact on child and parent anxiety level of a teddy bear-scale mock magnetic resonance scanner.

Background: Pediatric magnetic resonance imaging (MRI) can be stressful. Mock MR scanners have been proven to be effective in avoiding the use of general anesthesia.

Objectives: We prospectively evaluated the impact of a teddy bear-scale model of a mock MR scanner on the anxiety experienced by parents and their children during MRI without general anesthesia .

Recursive Decomposition of Electromyographic Signals With a Varying Number of Active Sources: Bayesian Modeling and Filtering.

Objective: This paper describes a sequential decomposition algorithm for single-channel intramuscular electromyography (iEMG) generated by a varying number of active motor neurons.

Methods: As in previous work, we establish a hidden Markov model of iEMG, in which each motor neuron spike train is modeled as a renewal process with inter-spike intervals following a discrete Weibull law and motor unit action potentials are modeled as impulse responses of linear time-invariant systems with known prior. We then expand this model by introducing an activation vector associated with the state vector of the hidden Markov model.

Training program for pain assessment in the newborn.

Aim: Pain management is correlated with pain assessment in the newborn infant. The aim of this study was to assess the impact of a 2-week training program composed of short (20min), repeated training sessions conducted in the unit.

Methods: Pain assessment was studied by means of audits.

[Maternal anxiety related to how the pediatrician provided prenatal information about preterm birth].

Introduction: Women hospitalized for preterm labor require clear information about prematurity. This study assessed whether or not specific written information about prematurity delivered at admission to the unit combined with an oral explanation from a pediatrician would decrease women's anxiety compared to an oral explanation alone.

Material And Methods: This was a prospective, single-center observational study.

Walking Gait Step Length Asymmetry Induced by Handheld Device.

The modeling and feature extraction of human gait motion are crucial in biomechanics studies, human localization, and robotics applications. Recent studies in pedestrian navigation aim at extracting gait features based on the data of low-cost sensors embedded in handheld devices, such as smartphones. The general assumption in pedestrian dead reckoning (PDR) strategy for navigation application is that the presence of a device in hand does not impact the gait symmetry and that all steps are identical.

Safety and tolerability of subcutaneous treprostinil in newborns with congenital diaphragmatic hernia and life-threatening pulmonary hypertension.

Background: Prolonged pulmonary hypertension (PH) is highly predictive for pulmonary morbidity and death in infants with congenital diaphragmatic hernia (CDH).

Objectives: To report the effects and tolerability of subcutaneous treprostinil in newborns with severe CDH and late life-threatening PH.

Methods: We recorded clinical and echocardiography data before and after starting subcutaneous treprostinil, on patients with severe CDH and late PH, refractory to inhaled nitric oxide and oral sildenafil.

Endocrine, metabolic, and behavioral effects of and recovery from acute stress in a free-ranging bird.

Acute stress in vertebrates generally stimulates the hypothalamo-pituitary-adrenal axis and is often associated with multiple metabolic changes, such as increased gluconeogenesis, and with behavioral alterations. Little information is available, especially in free-ranging organisms, on the duration of these reversible effects once animals are no longer exposed to the stressor. To investigate this question, we exposed free-ranging adult male Rufous-winged Sparrows, Peucaea carpalis, in breeding condition to a standard protocol consisting of a social challenge (conspecific song playback) followed with capture and restraint for 30min, after which birds were released on site.

The seasonal glucocorticoid response of male Rufous-winged Sparrows to acute stress correlates with changes in plasma uric acid, but neither glucose nor testosterone.

We sought to clarify functional relationships between baseline and acute stress-induced changes in plasma levels of the stress hormone corticosterone (CORT) and the reproductive hormone testosterone (T), and those of two main metabolites, uric acid (UA) and glucose (GLU). Acute stress in vertebrates generally stimulates the secretion of glucocorticoids, which in birds is primarily CORT. This stimulation is thought to promote behavioral and metabolic changes, including increased glycemia.

Innate immunity and testosterone rapidly respond to acute stress, but is corticosterone at the helm?

When faced with a stressor, vertebrates can rapidly increase the secretion of glucocorticoids, which is thought to improve the chances of survival. Concurrent changes in other physiological systems, such as the reproductive endocrine or innate immune systems, have received less attention, particularly in wild vertebrates. It is often thought that glucocorticoids directly modulate immune performance during a stress response, but, in many species, androgens also rapidly respond to stress.