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Objective: To recalculate biological effective dose values (BED) for radio-surgical treatments of acoustic neuroma from a previous study. BEDs values were previously overestimated by only using beam-on times in calculations, so excluding the important beam-off-times (when deoxyribonucleic acid repair continues) which contribute to the overall treatment time. Simple BED estimations using a mono-exponential approximation may not always be appropriate but if used should include overall treatment time., Methods: Time intervals between isocenters were estimated. These were especially important for the Gamma Knife Model 4C cases since manual changes significantly increase overall treatment times. Individual treatment parameters, such as iso-center number, beam-on-time, and beam-off-time, were then used to calculate BED values using a more appropriate bi-exponential model that includes fast and slow components of DNA damage repair over a wider time range., Results: The revised BED estimates differed significantly from previously published values. The overestimates of BED, obtained using beam-on-time only, varied from 0%-40.3%. BED subclasses, each with a BED range of 5 Gy 2.47 , indicated that revised values were consistently reduced when compared with originally quoted values, especially for 4C compared with Perfexion cases. Furthermore, subdivision of 4C cases by collimator number further emphasized the impact of scheduled gap times on BED. Further analysis demonstrated important limitations of the mono-exponential model. Target volume was a major confounding factor in the interpretation of the results of this study., Conclusions: BED values should be estimated by including beam-on and beam-off times. Suggestions are provided for more accurate BED estimations in future studies., (Copyright © 2022 The Author(s). Published by Elsevier Inc. All rights reserved.)

Purpose: Photon radiation therapy (RT) is important in the treatment of many brain tumors but can negatively affect neurocognition. Proton therapy (PT) can reduce doses to normal brain structures. We compared photon and proton plans to estimate the potential benefit in cognition if the patient were treated with PT., Materials and Methods: We analyzed 23 adult patients with proton and photon plans for the treatment of a primary brain tumor. Cognitive outcomes were predicted using converted equivalent dose (EQD2) with an α/β ratio of 3 to left temporal lobe and normal brain tissue. Risks of cognitive decline on 2 specific tests, the Controlled Oral Word Association Test (COWAT [letter S], a test of verbal fluency) and the Wechler Adult Intelligence Scale (WAIS-IV Coding Test, a test of processing speed) were derived from a previously published model., Results: Dose reductions to left temporal lobe and normal brain tissue translated into lower estimated probabilities of impairment in specific neurocognitive test scores after PT. With a mean dose reduction from 1490 to 1092 cGy in EQD2 to the left temporal lobe ( P < .001), there was reduction in probability of impairment in the COWAT (Letter S) test from 6.8% to 5.4%. Similar results were seen with the normal brain (750 to 451 cGy in EQD2, P < .001), with reduction in probability of impairment in the WAIS-IV Coding test from 5% to 4.1%. Other structures experiencing dose reduction with PT included each cochlea, posterior fossa, each temporal lobe, and each hippocampus., Conclusion: We confirmed an association between PT and lower doses to brain substructures, which is expected to result in a modest decrease in probability of impairment in neurocognitive test scoring. These findings should be confirmed in prospective cohorts of patients treated with PT., Competing Interests: Conflicts of Interest: Derek S. Tsang, MD, MSc, received travel support from Mevion Medical Systems and Elekta AB. The authors have no other relevant conflicts of interest to disclose., (©Copyright 2023 The Author(s).)

Objective: To evaluate the relationships between calibration dose rate, calculated biologically effective dose (BED), and clinical factors and tumor control after stereotactic radiosurgery (SRS) for acoustic neuroma., Methods: We performed a retrospective study of all patients with acoustic neuromas treated with frame-based cobalt-60 SRS at a single institution between 2005 and 2019. The calibration dose rate and cobalt-60 half-life were used to calculate the nominal dose rate during treatment. An SRS-specific monoexponential model accounting for treatment time per lesion was used to estimate BED., Results: The study included 607 patients with 612 acoustic neuromas. Median follow-up was 5.0 years. There was no association between dose rate or BED with local failure (LF), radiologic edema, or symptomatic edema. Cystic tumors (adjusted hazard ratio 0.26, P = 0.028) were associated with lower LF, while use of SRS as salvage treatment for growing tumors (adjusted hazard ratio 4.9, P < 0.0001) was associated with higher LF. LF occurred more frequently in larger-diameter tumors, while radiologic or symptomatic edema occurred more frequently in larger-volume tumors., Conclusions: Radiosurgery dose rate and BED were not associated with tumor control or radiologic or symptomatic edema. Salvage SRS and larger tumors were associated with a higher LF rate, while cystic tumors were associated with a lower LF rate. Patients with larger tumors should be counseled appropriately about potential side effects and when to seek follow-up care., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Purpose: At our institution, a multifaceted approach is used to reduce general anesthetic (GA) use for children receiving photon radiation therapy (RT) as standard-of-care treatment. The purpose of this study was to evaluate the effectiveness of our methods., Methods and Materials: Patients treated as part of the pediatric radiation therapy program from 2010 to 2018 were retrospectively reviewed. GA use was defined as need for intravenous propofol or inhaled gaseous anesthetic for at least 1 simulation or RT session. Methods to reduce GA use included presence of a dedicated pediatric nurse for procedural preparation, audiovisual distraction (television during RT), and 2-way audio communication with caregivers., Results: There were 779 unique patients who received RT over 14 163 fractions of radiation. GA utilization was 90% in those under age 3, 28% in those age 3 to 6, 1% in those age 7 to 11, and <1% in those ≥12 years of age. Four years of age is a cutoff age at which the majority of patients switch from needing GA (56.6% for those aged 3) to not needing GA (29.8% for those aged 4). Younger age, use of total body irradiation, and craniospinal irradiation were independently associated with requiring GA., Conclusions: Using methods designed to reduce GA use, most children aged 4 years or older were able receive RT awake. Our GA rates compare favorably to other literature reports; thus, pediatric RT centers should consider adopting specific interventions to reduce GA use., (Copyright © 2019 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.)

Background: Adult sellar atypical teratoid/rhabdoid tumor (ATRT) is a rare diagnosis that has recently been shown to be a clinicopathologically and genetically distinct variant of ATRT occurring almost exclusively in middle-aged women. Although up to one third of pediatric ATRT is caused by a familial syndrome, no previous cases of a familial adult sellar ATRT have been reported. We present the first case report of a familial germline mutation causing adult sellar ATRT and a literature review of 29 previously reported cases of sporadic adult sellar ATRT., Case Description: A 51-year-old woman with a family history of brain tumors spanning 3 generations presented with visual decline and was diagnosed with an adult sellar ATRT. Genetic studies showed a heterozygous splice-site loss-of-function mutation of the INI1 gene in exon 7. Treatment included endoscopic endonasal biopsy, craniospinal irradiation, and focal tumor boost, followed by adjuvant chemotherapy., Conclusions: This is the first case report of a familial germline mutation causing adult sellar ATRT. This article highlights the importance of a thorough family history and genetic testing in these individuals and reviews the current genetics, histopathology, and multidisciplinary treatment approach in this rare condition., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Introduction: RBApp is an educational software program that calculates the biologically effective dose and equivalent dose in 2-Gy fractions, permitting conversion between dose-fractionation schemes in radiation therapy. The purposes of this study were to describe the adoption and current patterns of use of this tool and evaluate user satisfaction with RBApp., Methods: RBApp is available as a native app for Android and BlackBerry and a web app for iOS and other devices. User and device characteristics were collected from app store dashboards and server logs; expected values were retrieved from StatCounter Global Stats. A voluntary web-based questionnaire was created to evaluate the patterns of use of RBApp. This questionnaire collected information on user demographics, purpose of use, and user satisfaction., Results: Over a 2.75-year period, there were 2,291 installations on Android and BlackBerry devices; 8,074 unique visits were logged to the web app; and 25 respondents completed the web-based questionnaire. Among this group, RBApp was used by radiation oncologists (44.0%), physicists (32.0%), and resident physicians (24.0%). It was used for clinical decision making by 78.3% of users, education and training by 43.5%, and research by 30.4%. Twenty of 22 users (90.9%) were satisfied with RBApp. A greater proportion of web app users used obsolete software to access the application compared with the rest of the global Internet population; 15.2% (95% confidence interval, 12.3%-18.6%) used Windows XP, and 16.0% (95% confidence interval, 13.0%-19.5%) used Internet Explorer 8.0 (expected global proportions 8.5% and 3.1%, respectively)., Conclusions: In this study, a mobile application for radiobiology calculations and its adoption by the radiation oncology community was evaluated. Users were satisfied with RBApp, and this tool is used for both clinical decision making and educational purposes. However, legacy software use remained prevalent, which may have implications for information security., (Copyright © 2015 Elsevier Inc. All rights reserved.)

The peroxisome proliferator-activated receptor alpha (PPARalpha) has been known to play a pivotal role in maintaining the energy balance during fasting; however, the battery of PPARalpha target genes involved in this metabolic response is still not fully characterized. Here, we report the identification and characterization of Ppsig (for PPARalpha-regulated and starvation-induced gene) with unknown biological function from mouse liver. Multiple Ppsig cDNAs which differed in the 3'-untranslated regions were identified. The open reading frame of Ppsig cDNA is 1830 bp which encodes a protein of 67.33 kDa. Ppsig contains 11 exons spanning at least 10 kb. Although the exact biological function of Ppsig is still not known, we found that Ppsig mRNA transcript was dramatically up-regulated during 72 h fasting and following treatment with a potent PPARalpha agonist, in a tissue-specific and PPARalpha-dependent manner. A functional peroxisome proliferator-response element was found in the intron 1 of Ppsig, thus confirming that Ppsig is a novel direct mouse PPARalpha target gene. This finding might help in elucidating the transcriptional regulatory mechanism of Ppsig in the cellular response to fasting.

Background: Operations for empyema thoracis are conventionally performed by open thoracotomy, whereas the video-assisted thoracic surgery (VATS) approach remains controversial. This study compares the radiologic and functional outcomes of decortication using the two approaches., Methods: During a 5-year period, 77 consecutive patients underwent decortication for empyema thoracis at two university teaching hospitals. The choice of surgical approach was decided by surgeon preference. Preoperative and postoperative empyema management was the same in all patients. Postoperative radiologic improvements were graded by a radiologist blinded to the approach used. Functional improvements were assessed by a questionnaire-based survey conducted at a mean of 36 months after the surgical procedure., Results: The VATS approach was used in 41 patients and the thoracotomy approach in 36 patients. Patients in the two groups had similar preoperative demographic and clinical features. No patients required conversion from VATS to thoracotomy or reintervention for empyema. Intraoperative blood loss, duration of chest drain, lengths of hospital stay, and postoperative complication rates were all similar in the two groups. The mean operation time in the VATS group was significantly shorter (2.5 versus 3.8 hours, p < 0.001). Decortication using both approaches gave similar degrees of postoperative radiologic and functional improvements. Of the 42 patients available for follow-up, the 21 who received the VATS approach reported significantly less postoperative pain (p = 0.04), greater satisfaction with the wounds (p < 0.0001), and greater satisfaction with the operation overall (p = 0.006)., Conclusions: VATS allows equally effective decortication for empyema as thoracotomy. However, the VATS approach gives less pain and greater patient acceptance.

The peroxisome proliferator-activated receptor alpha (PPARalpha) has been implicated as a key control of fatty acid catabolism during the cellular fasting. However, little is known regarding changes of individual fatty acids in hepatic triacylglycerol (TG) and phospholipid (PL) as a result of starvation. In the present work, the effects of 72 h fasting on hepatic TG and PL fatty acid profiles in PPARalpha-null (KO) mice and their wild-type (WT) counterparts were investigated. Our results indicated that mice deficient in PPARalpha displayed hepatomegaly and hypoketonemia following 72 h starvation. Histochemical analyses revealed that severe fatty infiltration was observed in the livers of KO mice under fasted conditions. Furthermore, 72 h fasting resulted in a 2.8-fold higher accumulation of hepatic TG in KO mice than in WT mice fasted for the same length of time. Surprisingly, the total hepatic PL contents in fasted KO mice decreased by 45%, but no significant change in hepatic PL content was observed in WT mice following starvation. Gas chromatographic analysis indicated that KO mice were deprived of arachidonic (20:4n-6) and docosahexaenoic (22:6n-3) acids during fasting. Taken together, these results show that PPARalpha plays an important role in regulation of fatty acid metabolism as well as phospholipid homeostasis during energy deprivation.

The method describes quantification and confirmation of flunixin in equine plasma by liquid chromatography-quadrupole time-of-flight mass spectrometry (LC/Q-TOF/MS/MS). Samples were screened by enzyme-linked immunosorbent assay (ELISA) and only those samples presumptively declared positive were subjected to quantification and confirmation for the presence of flunixin by this method. The method is also readily adaptable to instrumental screening for the analyte. Flunixin was recovered from plasma by liquid-liquid extraction (LLE). The sample was diluted with 2 ml saturated phosphate buffer (pH 3.10) prior to LLE. The dried extract was reconstituted in acetonitrile:water:formic acid (50:50:0.1, v/v/v) and subsequently analyzed on a Q-TOF tandem mass spectrometer (Micromass) operated under electrospray ionization positive ion mode. The concentration of flunixin was determined by the internal standard (IS) calibration method using the peak area ratio with clonixin as the IS. The limits of detection (LOD) and quantification (LOQ) for flunixin in equine plasma were 0.1 and 1 ng/ml, respectively, whereas the limit of confirmation (LOC) was 2.5 ng/ml. The qualifying ions for the identification of flunixin were m/z 297 [M+H](+), 279 (BP), 264, 259, 239 and those for clonixin (IS) were m/z 263 [M+H](+), 245 (BP) and 210. The measurement uncertainty about the result was 8.7%. The method is simple, sensitive, robust and reliably fast in the quantification and confirmation of flunixin in equine plasma. Application of this method will assist racing authorities in the enforcement of tolerance plasma concentration of flunixin in the racehorse on race day.

A reliable and sensitive method for the extraction and quantification of phenytoin (5,5'-diphenylhydantoin), its major metabolite, 5-(p-hydroxyphenyl)-5-phenylhydantoin (p-HPPH) and minor metabolite, 5-(m-hydroxyphenyl)-5-phenylhydantoin (m-HPPH) in horse urine and plasma is described. The method involves the use of solid-phase extraction (SPE), liquid-liquid extraction (LLE), enzyme hydrolysis (EH) and high-performance liquid chromatography (HPLC). The minor metabolite, 5-(m-hydroxyphenyl)-5-phenylhydantoin (m-HPPH) was not present in a reliably quantifiable concentration in all samples. The new method described was successfully applied in the pharmacokinetic studies and elimination profile of phenytoin and p-HPPH following oral or intravenous administration in the horse.