Anastrozole improves height outcomes in growing children with congenital adrenal hyperplasia due to 21-OHD.

Background: Hyperandrogenemia resulting in estrogen-mediated accelerated bone maturation and early growth plate fusion contributes to short stature in children with congenital adrenal hyperplasia (CAH) due to 21OHD. Aromatase inhibitors block androgen conversion to estrogen and have been used off-label in children with short stature to improve adult height. There are no adequately powered studies examining the use of aromatase inhibitors in children with CAH with advanced bone age and reduced predicted adult height.

Case Report: Contiguous presentation of anti-MDA5 juvenile dermatomyositis and anti-AQP4 neuromyelitis optica spectrum disorder in an adolescent patient.

Neuromyelitis optica spectrum disorder (NMOSD) is a rare inflammatory disorder of the central nervous system (CNS) that is known to be associated with other neurologic and organ-specific autoimmune conditions. There has been increasing recognition of the association between NMOSD and systemic autoimmune disease, most commonly systemic lupus erythematosus and Sjogren's syndrome. We report a case of an adolescent presenting with anti-melanoma differentiation-associated protein 5 juvenile dermatomyositis (anti-MDA5 JDM) and NMOSD, exhibiting clinical features of myelitis, polyarthritis, myositis, and skin involvement.

An AI-based universal phantom analysis method based on XML-SVG wireframes with novel functional object identifiers.

Quality assurance (QA) testing must be performed at regular intervals to ensure that medical devices are operating within designed specifications. Numerous QA phantoms and software packages have been developed to facilitate measurements of machine performance. However, due to the hard-coded nature of geometric phantom definition in analysis software, users are typically limited to the use of a small subset of compatible QA phantoms.

Radiation-Chemical Oxygen Depletion Depends on Chemical Environment and Dose Rate: Implications for the FLASH Effect.

Purpose: FLASH (dose rates >40 Gy/s) radiation therapy protects normal tissues from radiation damage, compared with conventional radiation therapy (∼Gy/m). Radiation-chemical oxygen depletion (ROD) occurs when oxygen reacts with radiation-induced free radicals, so a possible mechanism for FLASH involves radioprotection by the decreased oxygen as ROD occurs. High ROD rates would favor this mechanism, but prior studies have reported low ROD values (∼0.

The association among SES, screen time, and outdoor play in children at different ages: The GECKO Drenthe study.

Introduction: This study examined the association among socioeconomic status (SES), screen time, and outdoor play in children at different ages in the GECKO Drenthe birth cohort study.

Methods: Valid data were obtained from two surveys at ages 3-4 years and 10-11 years. Screen time (TV watching and computer use) and outdoor play were reported by parents.

A phenomenological model of proton FLASH oxygen depletion effects depending on tissue vasculature and oxygen supply.

Introduction: Radiation-induced oxygen depletion in tissue is assumed as a contributor to the FLASH sparing effects. In this study, we simulated the heterogeneous oxygen depletion in the tissue surrounding the vessels and calculated the proton FLASH effective-dose-modifying factor (FEDMF), which could be used for biology-based treatment planning.

Methods: The dose and dose-weighted linear energy transfer (LET) of a small animal proton irradiator was simulated with Monte Carlo simulation.

Oxygen Monitoring in Model Solutions and In Vivo in Mice During Proton Irradiation at Conventional and FLASH Dose Rates.

FLASH is a high-dose-rate form of radiation therapy that has the reported ability, compared with conventional dose rates, to spare normal tissues while being equipotent in tumor control, thereby increasing the therapeutic ratio. The mechanism underlying this normal tissue sparing effect is currently unknown, however one possibility is radiochemical oxygen depletion (ROD) during dose delivery in tissue at FLASH dose rates. In order to investigate this possibility, we used the phosphorescence quenching method to measure oxygen partial pressure before, during and after proton radiation delivery in model solutions and in normal muscle and sarcoma tumors in mice, at both conventional (Conv) (∼0.

Improving the efficiency of small animal 3D-printed compensator IMRT with beamlet intensity total variation regularization.

Purpose: There is growing interest in the use of modern 3D printing technology to implement intensity-modulated radiation therapy (IMRT) on the preclinical scale that is analogous to clinical IMRT. However, current 3D-printed IMRT methods suffer from complex modulation patterns leading to long delivery times, excess filament usage, and less accurate compensator fabrication. In this work, we have developed a total variation regularization (TVR) approach to address these issues.

Ultrafast Tracking of Oxygen Dynamics During Proton FLASH.

Purpose: Radiation therapy delivered at ultrafast dose rates, known as FLASH RT, has been shown to provide a therapeutic advantage compared with conventional radiation therapy by selectively protecting normal tissues. Radiochemical depletion of oxygen has been proposed to underpin the FLASH effect; however, experimental validation of this hypothesis has been lacking, in part owing to the inability to measure oxygenation at rates compatible with FLASH.

Methods And Materials: We present a new variant of the phosphorescence quenching method for tracking oxygen dynamics with rates reaching up to ∼3.

Night-time Screen Media Use in the Pediatric Intensive Care Unit.

This prospective observational study quantified screen media use within the night-time pre-sleep period in a pediatric intensive care unit and postulated possible implications. Seventy-five patients between the ages of newborn to 19 years old were observed 5 evenings per week for 3 weeks. Trained observers documented the patient's screen use, type of screen used, screen engagement, sleep state, light level, and parental presence.

Characterization of a high-resolution 2D transmission ion chamber for independent validation of proton pencil beam scanning of conventional and FLASH dose delivery.

Introduction: Ultra-high dose rate (FLASH) radiotherapy has become a popular research topic with the potential to reduce normal tissue toxicities without losing the benefit of tumor control. The development of FLASH proton pencil beam scanning (PBS) delivery requires accurate dosimetry despite high beam currents with correspondingly high ionization densities in the monitoring chamber. In this study, we characterized a newly designed high-resolution position sensing transmission ionization chamber with a purpose-built multichannel electrometer for both conventional and FLASH dose rate proton radiotherapy.

Small Animal IMRT Using 3D-Printed Compensators.

Purpose: Preclinical radiation replicating clinical intensity modulated radiation therapy (IMRT) techniques can provide data translatable to clinical practice. For this work, treatment plans were created for oxygen-guided dose-painting in small animals using inverse-planned IMRT. Spatially varying beam intensities were achieved using 3-dimensional (3D)-printed compensators.

Adiposity and High Blood Pressure during Childhood: A Prospective Analysis of the Role of Physical Activity Intensity and Sedentary Time in the GECKO Drenthe Cohort.

Whereas in adults, physical inactivity is strongly related to obesity and hypertension, in young children the evidence is inconsistent and scarce. We examined the association between physical activity (PA) behaviours at 5-6 years of age and adiposity and blood pressure (BP) at 10-11 years in 947 children (51% boys) from the Groningen Expert Center for Kids with Obesity (GECKO) Drenthe cohort. Sedentary time (ST) and light, moderate, and vigorous PA were assessed using accelerometry (ActiGraph GT3X, wear time > 600 min/day, ≥3 days).

Current delivery limitations of proton PBS for FLASH.

Purpose: Proton Pencil Beam Scanning (PBS) is an attractive solution to realize the advantageous normal tissue sparing elucidated from FLASH high dose rates. The mechanics of PBS spot delivery will impose limitations on the effective field dose rate for PBS.

Methods: This study incorporates measurements from clinical and FLASH research beams on uniform single energy and the spread-out Bragg Peak PBS fields to extrapolate the PBS dose rate to high cyclotron beam currents 350, 500, and 800 nA.

Mechanism and Model of a Soft Robot for Head Stabilization in Cancer Radiation Therapy.

We present a parallel robot mechanism and the constitutive laws that govern the deformation of its constituent soft actuators. Our ultimate goal is the real-time motion-correction of a patient's head deviation from a target pose where the soft actuators control the position of the patient's cranial region on a treatment machine. We describe the mechanism, derive the stress-strain constitutive laws for the individual actuators and the inverse kinematics that prescribes a given deformation, and then present simulation results that validate our mathematical formulation.

The Effect of a Personalized Newsletter to Physical Therapists on Patient Recruitment: A Cluster Randomized Trial in Primary Physiotherapy Care.

Objective: To assess the effect of a personalized newsletter compared with a standard newsletter on patient recruitment in physiotherapy research.

Methods: We performed a cluster-randomized trial including 120 physiotherapists who recruited patients for a prospective cohort and were randomly assigned to either receiving personalized feedback in a newsletter (intervention group) or a standard newsletter (control group). We calculated the difference in the number of patients included in the study corrected for inclusion time between both groups.

Effects of physical activity interventions on cognitive outcomes and academic performance in adolescents and young adults: A meta-analysis.

The aim was to provide a meta-analysis of studies investigating the effects of physical activity interventions on cognitive outcomes and academic performance in adolescents or young adults. A systematic review with meta-analysis was performed using the following databases: Embase, ERIC, MEDLINE, PsycINFO and Web of Science. Studies had to meet the following criteria: controlled study design, investigating the effects of physical activity interventions on cognitive outcomes and academic performance in healthy adolescents or young adults (12-30 years).

Unravelling the association between accelerometer-derived physical activity and adiposity among preschool children: A systematic review and meta-analyses.

Evidence on the association between physical activity (PA) and adiposity in young children is inconclusive. A systematic review and meta-analyses were conducted to examine associations between accelerometer-derived PA and varying adiposity outcomes in preschool children. Searches were conducted in Embase, MEDLINE and Web of Science to identify studies on the association between total PA, sedentary behaviour or different PA intensities and adiposity in children aged 2 to 7 years.

Physical activity around the clock: objectively measured activity patterns in young children of the GECKO Drenthe cohort.

Background: Given the widespread problem of physical inactivity, and the continued growth in prevalence of childhood and adolescent obesity, promotion of regular physical activity (PA) among young people has become a public priority. A greater understanding of children's PA patterns throughout the day is needed to effectively encourage children to be more physically active. Hence this study looking at the distribution of PA in young children throughout the day and its relevance to overweight.

A conceptual study on real-time adaptive radiation therapy optimization through ultra-fast beamlet control.

A central problem in the field of radiation therapy (RT) is how to optimally deliver dose to a patient in a way that fully accounts for anatomical position changes over time. As current RT is a static process, where beam intensities are calculated before the start of treatment, anatomical deviations can result in poor dose conformity. To overcome these limitations, we present a simulation study on a fully dynamic real-time adaptive radiation therapy (RT-ART) optimization approach that uses ultra-fast beamlet control to dynamically adapt to patient motion in real-time.

Optimization based trajectory planning for real-time 6DoF robotic patient motion compensation systems.

Purpose: Robotic stabilization of a therapeutic radiation beam with respect to a dynamically moving tumor target can be accomplished either by moving the radiation source, the patient, or both. As the treatment beam is on during this process, the primary goal is to minimize exposure of normal tissue to radiation as much as possible when moving the target back to the desired position. Due to the complex mechanical structure of 6 degree-of-freedom (6DoF) robots, it is not intuitive as to what 6 dimensional (6D) correction trajectory is optimal in achieving such a goal.

Use of a laser-guided collimation system to perform direct kilovoltage x-ray spectra measurements on a linear accelerator onboard imager.

Purpose: The increased use of image-guided radiation therapy (IGRT) has led to increased use of kV on board imaging (OBI) devices. At present, directly measured OBI beam quality data have only been reported in terms of half-value layers (HVL). However, the HVL metric alone does not give the full OBI energy spectra as needed for accurate beam modeling.