This paper proposes a model for the angular dependency of MatriXX response and investigates whether MatriXX, with the angular-model-based approach can be applied to true composite dose verification for IMRT plans. Method: This model attributes the angular dependence of MatriXX response to dynamical translation of its effective measurement plane (EMP) due to the change of beam angle. Considering this mechanism, true composite dose verifications for IMRT plans specified in AAPM TG 119 report using both MatriXX and Gafchromic EBT3 films were undertook and compared to validate the applicability of MatriXX for patient specific QA of composite beam IMRT plans. Dose verifications using MatriXX with and without angular-model-based approach were performed. Results: MatriXX with angular-model-based approach achieved gamma passing rates with 3%/3 mm and 3%/2 mm criteria better than 98.3% and 98.1% respectively for true composite dose verification of plans in AAPM TG 119 report.The 3%/3 mm and 3%/2 mm gamma passing rates using MatriXX without angular-model-based approach ranged from 85.8% to 98.2% and from 81.3% to 96.5%, respectively. The p-values from the single sided paired t-test indicated no statistical difference between the passing rates from MatriXX with angularmodel-based approach and from films, and significant difference between the passing rates from uncorrected MatriXX and from films. Conclusion:The proposed model for angular dependent MatriXX response is necessary and effective. Dose verification using MatriXX withThis is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

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Background: Substance P (SP) contributes to the pathogenesis of pain by acting on neurokinin‐1 receptor (NK-1R), specialized sensory neurons that detect noxious stimuli. Aprepitant, an antagonist of NK-1R widely used to treat chemotherapy-induced nausea and vomiting. In this study, we assessed aprepitant’s analgesic effect on inflammatory pain in mice and its mechanism of action in spinal cord.Methods: The excitability of DRG neurons treatment with aprepitant was measured using whole-cell patch-clamp recordings. The inflammatory pain model was induced in adult ICR mice by a single dose intraplantar injection of formalin and carrageenan. The mice were treated with aprepitant, and the behavioral tests were measured after the intraperitoneal injection of aprepitant. The morphological changes on inflamed paw tissues were determined by using hematoxylin eosin staining. The mRNA expressions of MCP-1, TNF-α, IL-6, IL-1β, and NF-κBp65 were measured by real-time quantitative PCR analysis. Changes in the protein expression levels were assayed using enzyme linked immunosorbent assay. Western blotting and immunohistochemistry were used to assay the cell signaling.Results: Aprepitant treatment showed a significantly higher AP threshold in vitro. In vivo, the aprepitant showed a significant anti-inflammatory and analgesia effect in the mice with inflammatory pain. After the administration of aprepitant, the paw tissues inflammatory damage was significantly relived. The mRNA levels of MCP-1, TNF-α, IL-6, IL-1β, and NF-κBp65 were down-regulate following aprepitant treatment. Meanwhile, aprepitant significantly suppressed over-expression of proinflammatory cytokines, as well as the phosphorylation of JNK and p38 MAPK in the spinal cord.Conclusions: The present study suggests that the extract of aprepitant attenuates inflammatory pain in mice via suppressing the phosphorylation of JNK and p38, and inhibiting the NF-κB signaling pathway.