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OPTIma: simplifying calorimetry for proton computed tomography in high proton flux environments. Phys Med Biol 2024; 69:055034. [PMID: 38346338 DOI: 10.1088/1361-6560/ad2883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 02/12/2024] [Indexed: 03/01/2024]
Abstract
Objective.Proton computed tomography (pCT) offers a potential route to reducing range uncertainties for proton therapy treatment planning, however the current trend towards high current spot scanning treatment systems leads to high proton fluxes which are challenging for existing systems. Here we demonstrate a novel approach to energy reconstruction, referred to as 'de-averaging', which allows individual proton energies to be recovered using only a measurement of their integrated energy without the need for spatial information from the calorimeter.Approach.The method is evaluated in the context of the Optimising Proton Therapy through Imaging (OPTIma) system which uses a simple, relatively inexpensive, scintillator-based calorimeter that reports only the integrated energy deposited by all protons within a cyclotron period, alongside a silicon strip based tracking system capable of reconstructing individual protons in a high flux environment. GEANT4 simulations have been performed to examine the performance of such a system at a modern commercial cyclotron facility using aσ≈ 10 mm beam for currents in the range 10-50 pA at the nozzle.Main results.Apart from low-density lung tissue, a discrepancy of less than 1% on the Relative Stopping Power is found for all other considered tissues when embedded within a 150 mm spherical Perspex phantom in the 10-30 pA current range, and for some tissues even up to 50 pA.Significance.By removing the need for the calorimeter system to provide spatial information, it is hoped that the de-averaging approach can facilitate clinically relevant, cost effective and less complex calorimeter systems for performing high current pCTs.
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Review of the validity of DOPS as an assessment tool for the procedural skills of surgical trainees. Ann R Coll Surg Engl 2023; 105:599-606. [PMID: 36374304 PMCID: PMC10471438 DOI: 10.1308/rcsann.2022.0052] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/25/2022] [Indexed: 09/02/2023] Open
Abstract
INTRODUCTION Surgical trainees at all stages are mandated to use workplace-based assessments (WBAs) to gain feedback from their trainers. Direct observation of procedural skills (DOPS) is a tool to assess hands-on surgical skills. This review of the literature seeks to ascertain how valid DOPS are as an assessment tool for the procedural skills of surgical trainees according to the American Psychology Association (APA) validity framework. METHODS Relevant literature was identified through a structured search of Medline, CINAHL and Web of Science databases, with further papers included on citation review. Following this, papers meeting the inclusion and exclusion criteria were included in the final review specifying those investigating WBAs including DOPS, assessments in practice rather than simulation and specifically for postgraduate surgical trainees. FINDINGS Sixteen papers were included in the final analysis. Extracted data from the returned papers were assessed for evidence of validity in each of the five domains on the APA framework: validity based on consequence, response process, reliability, content and relationship to other variables. There are studies that show good parameters for reliability and validity for specific DOPS used in endoscopy and otolaryngology. However, there is confusion over the purpose of DOPS among trainers and trainees as to whether they should be used formatively or summatively. Recent changes to the surgical curriculum have sought to address this, and further work into the impact of this needs to be done.
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Two-year review of firearm-related DNA casework evidence: a triage process to improve quality and efficiency. Forensic Sci Int 2022; 341:111516. [DOI: 10.1016/j.forsciint.2022.111516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Accepted: 11/08/2022] [Indexed: 11/10/2022]
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A Selective Adenylyl Cyclase 1 Inhibitor Relieves Pain Without Causing Tolerance. Front Pharmacol 2022; 13:935588. [PMID: 35899113 PMCID: PMC9310748 DOI: 10.3389/fphar.2022.935588] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Accepted: 06/20/2022] [Indexed: 11/13/2022] Open
Abstract
Among the ten different adenylyl cyclase isoforms, studies with knockout animals indicate that inhibition of AC1 can relieve pain and reduce behaviors linked to opioid dependence. We previously identified ST034307 as a selective inhibitor of AC1. The development of an AC1-selective inhibitor now provides the opportunity to further study the therapeutic potential of inhibiting this protein in pre-clinical animal models of pain and related adverse reactions. In the present study we have shown that ST034307 relives pain in mouse models of formalin-induced inflammatory pain, acid-induced visceral pain, and acid-depressed nesting. In addition, ST034307 did not cause analgesic tolerance after chronic dosing. We were unable to detect ST034307 in mouse brain following subcutaneous injections but showed a significant reduction in cAMP concentration in dorsal root ganglia of the animals. Considering the unprecedented selectivity of ST034307, we also report the predicted molecular interaction between ST034307 and AC1. Our results indicate that AC1 inhibitors represent a promising new class of analgesic agents that treat pain and do not result in tolerance or cause disruption of normal behavior in mice. In addition, we outline a unique binding site for ST034307 at the interface of the enzyme’s catalytic domain.
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SO-18 Reinforcing clinical outcomes with patient-reported QoL outcomes in patients with mCRC receiving FTD/TPI: Pooled analysis of PRECONNECT and TALLISUR studies. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.04.417] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Successful HeartMate III LVAD Implantation Despite Large Intra-Atrial Thrombus. J Heart Lung Transplant 2022. [DOI: 10.1016/j.healun.2022.01.1194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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A novel range telescope concept for proton CT. Phys Med Biol 2022; 67. [DOI: 10.1088/1361-6560/ac4b39] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Accepted: 01/13/2022] [Indexed: 11/11/2022]
Abstract
Abstract
Proton beam therapy can potentially offer improved treatment for cancers of the head and neck and in paediatric patients. There has been a sharp uptake of proton beam therapy in recent years as improved delivery techniques and patient benefits are observed. However, treatments are currently planned using conventional x-ray CT images due to the absence of devices able to perform high quality proton computed tomography (pCT) under realistic clinical conditions. A new plastic-scintillator-based range telescope concept, named ASTRA, is proposed here to measure the proton’s energy loss in a pCT system. Simulations conducted using GEANT4 yield an expected energy resolution of 0.7%. If calorimetric information is used the energy resolution could be further improved to about 0.5%. In addition, the ability of ASTRA to track multiple protons simultaneously is presented. Due to its fast components, ASTRA is expected to reach unprecedented data collection rates, similar to 108 protons/s. The performance of ASTRA has also been tested by simulating the imaging of phantoms. The results show excellent image contrast and relative stopping power reconstruction.
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MA14.03 Genomic Profiles and Potential Determinants of Response and Resistance in KRAS p.G12C-mutated NSCLC Treated With Sotorasib. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.08.184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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PS01.07 Registrational Phase 2 Trial of Sotorasib in KRAS p.G12C Mutant NSCLC: First Disclosure of the Codebreak 100 Primary Analysis. J Thorac Oncol 2021. [DOI: 10.1016/j.jtho.2021.01.321] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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SO-24 AMG 510, a novel small molecule inhibitor of KRAS G12C, for patients with advanced gastrointestinal cancers: Results from the CodeBreak 100 phase 1 trial. Ann Oncol 2020. [DOI: 10.1016/j.annonc.2020.04.039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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P-78 Early tumour shrinkage, depth of response and survival outcomes for RAS wild-type metastatic colorectal cancer patients classified by baseline tumour load: Retrospective pooled analysis of panitumumab PRIME/PEAK studies. Ann Oncol 2020. [DOI: 10.1016/j.annonc.2020.04.160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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A Selective AC1 Inhibitor as Non‐GPCR‐ or Ion Channel‐Dependent Approach for the Treatment of Pain. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.00596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Comparison of Oxidizing Solutions in the Evaluation of Metmyoglobin Reducing Activity in Dark-Cutting Beef. MEAT AND MUSCLE BIOLOGY 2019. [DOI: 10.22175/mmb.10736] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
ObjectivesMetmyoglobin reducing activity (MRA) is an inherent muscle biochemical property that can influence color stability. Hence, MRA is used in color research to better understand meat color changes. A greater postmortem muscle pH can affect inherent biochemical properties, including the conventional methodologies to determine MRA. The MRA methodology described in the American Meat Science Association Color Guide utilize changes in nitric oxide induced-metmyoglobin level pre- and post-incubation. However, a greater muscle pH can limit initial metmyoglobin formation. Hence, the methodology discussed in the AMSA color guide may not provide accurate results. Therefore, the objectives of this research were to compare different conditions to induce initial metmyoglobin formation.Materials and MethodsIn the first objective, normal-pH and dark-cutting steaks were dipped in 0.3%s (level recommended in the AMSA color guide) and 1% nitrite solution to induce metmyoglobin formation. Metmyoglobin formed steaks were blotted dry, vacuum packaged, and incubated at 30°C to induce metmyoglobin reduction. In the second experiment, 1% ferricyanide solution was used as an oxidizing agent. The methodology used in objective 1 was used to measure MRA. The experiments were replicated three times and the data were analyzed using the Mixed Procedure of SAS.ResultsThere was no effect (P > 0.05) of nitrite concentration on MRA of dark-cutting beef. However, when 1% ferricyanide was used as an oxidizing agent, initial metmyoglobin was more (P < 0.05) in dark-cutting beef compared with 0.3% sodium nitrite solution.ConclusionThe results suggest that the use of a strong oxidizing agent can impart more metmyoglobin formation in high-pH/dark-cutting beef.
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OA01.06 Safety, Efficacy, and Pharmacokinetics of AMG 510, a Novel KRASG12C Inhibitor, in Patients with Non-Small Cell Lung Cancer. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.09.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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OA02.02 Phase 1 Study of Safety, Tolerability, PK and Efficacy of AMG 510, a Novel KRASG12C Inhibitor, Evaluated in NSCLC. J Thorac Oncol 2019. [DOI: 10.1016/j.jtho.2019.08.412] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Early tumour shrinkage (ETS), depth of response (DpR) and associated survival outcomes in patients (pts) with RAS wild type (WT) metastatic colorectal cancer (mCRC) classified according to Köhne prognostic category: Retrospective analysis of the panitumumab (Pmab) PRIME study. Ann Oncol 2019. [DOI: 10.1093/annonc/mdz246.049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Uncovering Cell-Specific Mechanisms in Sex Differences in TLR4-Dependent Pain. THE JOURNAL OF PAIN 2019. [DOI: 10.1016/j.jpain.2019.01.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Adenylyl cyclase 7 and neuropsychiatric disorders: A new target for depression? Pharmacol Res 2019; 143:106-112. [PMID: 30904753 DOI: 10.1016/j.phrs.2019.03.015] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2018] [Revised: 03/14/2019] [Accepted: 03/19/2019] [Indexed: 12/28/2022]
Abstract
Adenylyl cyclases (ACs) are enzymes that catalyze the production of cyclic adenosine monophosphate (cAMP) from adenosine triphosphate (ATP). Humans express nine isoforms of membranous ACs and a soluble AC. Studies with genetic knockout or overexpression rodent models have indicated that AC isoforms may be targeted to achieve specific therapeutic outcomes. AC1, for instance, has been suggested and pursued as a target for relieving pain. Notably, previous studies examining genetically modified mice as well as human genetic polymorphisms have suggested a link between AC7 activity and depressive disorders. In the present review we present an overview on AC function and discuss the most recent developments to target AC isoforms for drug therapies. We next focus on discussing the available literature on the molecular and animal pharmacology of AC7 highlighting the available studies on the role of AC7 in depressive disorders. In addition, we discuss other possible physiological functions of AC7 relating to ethanol effects and the immune system and conclude with considerations about pharmacological modulation of AC7.
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Comparison of Oxidizing Solutions in the Evaluation of Metmyoglobin Reducing Activity in Dark-Cutting Beef. MEAT AND MUSCLE BIOLOGY 2019. [DOI: 10.22175/mmb2019.0177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
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Hypertension as a predictor of advanced colorectal cancer outcome and cetuximab treatment response. ACTA ACUST UNITED AC 2018; 25:e516-e526. [PMID: 30607118 DOI: 10.3747/co.25.4069] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Background Adrenergic receptor stimulation is involved in the development of hypertension (htn) and has been implicated in cancer progression and dissemination of metastases in various tumours, including colon cancer. Adrenergic antagonists such as beta-blockers (bbs) demonstrate inhibition of invasion and migration in colon cancer cell lines and have been associated with decreased mortality in colorectal cancer (crc). We examined the association of baseline htn and bb use with overall (os) and progression-free survival (pfs) in patients with pretreated, chemotherapy refractory, metastatic crc (mcrc). We also examined baseline htn as a predictor of cetuximab efficacy. Methods Using data from the Canadian Cancer Trials Group co.17 study [cetuximab vs. best supportive care (bsc)], we coded baseline htn and use of anti-htn medications, including bbs, for 572 patients. The chi-square test was used to assess the associations between those variables and baseline characteristics. Cox regression models were used for univariate and multivariate analyses of os and pfs by htn diagnosis and bb use. Results Baseline htn, bb use, and anti-htn medication use were not found to be prognostic for improved os. Baseline htn and bb use were not significant predictors of cetuximab benefit. Conclusions In chemorefractory mcrc, neither baseline htn nor bb use is a significant prognostic factor. Baseline htn and bb use are not predictive of cetuximab benefit. Further investigation to determine whether baseline htn or bb use have a similarly insignificant impact on prognosis in patients receiving earlier lines of treatment remains warranted.
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Early tumour shrinkage (ETS) and its impact on tumour-related symptoms in patients with previously untreated RAS wild-type metastatic colorectal cancer (mCRC): A retrospective analysis of three panitumumab studies. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy150.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Safety and efficacy of trifluridine/tipiracil in previously treated metastatic colorectal cancer (mCRC): Preliminary results from the phase IIIb, international, open-label, early-access PRECONNECT study. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy149.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Patterns of care and clinical outcomes for gastric and gastro-oesophageal cancers in South Australian population: Initial results of a state-wide audit. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy151.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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PETACC-6: Preop chemoradiation and postop chemotherapy (capecitabine +/- oxaliplatin) in locally advanced rectal cancer: Overall survival after long term follow-up. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy149.018] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Multiple breath washout in pediatric patients after lung transplantation. Am J Transplant 2018; 18:145-153. [PMID: 28719135 DOI: 10.1111/ajt.14432] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 07/06/2017] [Accepted: 07/11/2017] [Indexed: 01/25/2023]
Abstract
Forced expiratory volume in 1 second (FEV1 ) from spirometry is the most commonly used parameter to detect early allograft dysfunction after lung transplantation (LTx). There are concerns regarding its sensitivity. Nitrogen-multiple breath washout (N2 -MBW) is sensitive at detecting early global (lung clearance index [LCI]) and acinar (Sacin ) airway inhomogeneity. We investigated whether N2 -MBW indices indicate small airways pathology after LTx in children with stable spirometry. Thirty-seven children without bronchiolitis obliterans syndrome [BOS] at a median of 1.6 (0.6-3.0) years after LTx underwent N2 -MBW and spirometry, 28 of those on 2 occasions (≤6 months apart) during clinically stable periods. Additional longitudinal data (11 and 8 measurements, respectively) are provided from 2 patients with BOS. In patients without BOS, LCI and Sacin were significantly elevated compared with healthy controls. LCI was abnormal at the 2 test occasions in 81% and 71% of patients, respectively, compared with 30% and 39% of patients with abnormal FEV1 /forced vital capacity (FVC). Correlations of LCI with FEV1 /FVC (r = 0.1, P = .4) and FEV1 (r = -0.1, P = .6) were poor. N2 -MBW represents a sensitive and reproducible tool for the early detection of airways pathology in stable transplant recipients. Moreover, indices were highly elevated in both patients with BOS. Spirometry and LCI showed poor correlation, indicating distinct and complementary physiologic measures.
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Abstract ID: 171 A Monte Carlo study to reduce range uncertainty in proton beam therapy via prompt gamma-ray detection. Phys Med 2018; 45 Suppl 1:S2. [DOI: 10.1016/j.ejmp.2017.11.027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Prospective randomized trial of neoadjuvant chemotherapy during the 'wait period' following preoperative chemoradiotherapy for rectal cancer: results of the WAIT trial. Colorectal Dis 2017; 19:973-979. [PMID: 28503826 DOI: 10.1111/codi.13724] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/15/2016] [Accepted: 03/13/2017] [Indexed: 02/08/2023]
Abstract
AIM The aim was to determine whether the addition of additional cycles of chemotherapy during the 'wait period' following neoadjuvant chemoradiotherapy for rectal cancer improves the pathological complete response (pCR) rate. METHOD Rectal cancer patients were randomly allocated either to a standard 10 week wait period before surgery (standard chemoradiotherapy, SCRT) or to receive three cycles of fluorouracil based chemotherapy following chemoradiotherapy during a similar 10 week wait (extended chemoradiotherapy, XCRT). The primary end-point was pCR as determined by blinded pathological assessment. RESULTS Forty-nine patients were randomized (SCRTn = 24, XCRTn = 25). pCR occurred in 10 patients overall but there was no significant difference in pCR between the groups (SCRTn = 6, XCRTn = 4, P = 0.49). CONCLUSION The addition of three cycles of 5-fluorouracil/leucovorin in a 10 week wait period after conventional chemoradiotherapy seems to result in similar pCR rates in patients with locally advanced rectal cancer based on this small randomized trial.
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(137) Meningeal application of prolactin and CGRP produces female specific migraine-related behavior in rodents. THE JOURNAL OF PAIN 2017. [DOI: 10.1016/j.jpain.2017.02.043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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An experimental demonstration of a new type of proton computed tomography using a novel silicon tracking detector. Med Phys 2017; 43:6129. [PMID: 27806609 DOI: 10.1118/1.4965809] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Radiography and tomography using proton beams promise benefit to image guidance and treatment planning for proton therapy. A novel proton tracking detector is described and experimental demonstrations at a therapy facility are reported. A new type of proton CT reconstructing relative "scattering power" rather than "stopping power" is also demonstrated. Notably, this new type of imaging does not require the measurement of the residual energies of the protons. METHODS A large area, silicon microstrip tracker with high spatial and temporal resolution has been developed by the Proton Radiotherapy Verification and Dosimetry Applications consortium and commissioned using beams of protons at iThemba LABS, Medical Radiation Department, South Africa. The tracker comprises twelve planes of silicon developed using technology from high energy physics with each plane having an active area of ∼10 × 10 cm segmented into 2048 microstrips. The tracker is organized into four separate units each containing three detectors at 60° to one another creating an x-u-v coordinate system. Pairs of tracking units are used to reconstruct vertices for protons entering and exiting a phantom containing tissue equivalent inserts. By measuring the position and direction of each proton before and after the phantom, the nonlinear path for each proton through an object can be reconstructed. RESULTS Experimental results are reported for tracking the path of protons with initial energies of 125 and 191 MeV. A spherical phantom of 75 mm diameter was imaged by positioning it between the entrance and exit detectors of the tracker. Positions and directions of individual protons were used to create angular distributions and 2D fluence maps of the beam. These results were acquired for 36 equally spaced projections spanning 180°, allowing, for the first time, an experimental CT image based upon the relative scattering power of protons to be reconstructed. CONCLUSIONS Successful tracking of protons through a thick target (phantom) has demonstrated that the tracker discussed in this paper can provide the precise directional information needed to perform proton radiography and tomography. When synchronized with a range telescope, this could enable the reconstruction of proton CT images of stopping power. Furthermore, by measuring the deflection of many protons through a phantom, it was demonstrated that it is possible to reconstruct a new kind of CT image (scattering power) based upon this tracking information alone.
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Venous thromboembolism in patients with esophageal or gastric cancer undergoing neoadjuvant chemotherapy. Dis Esophagus 2017; 30:1-7. [PMID: 27878904 DOI: 10.1111/dote.12516] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
There is a well-established link between cancer and venous thromboembolism (VTE), and patients receiving chemotherapy for esophageal or gastric cancer appear at high risk of developing VTE. The incidence of VTE in the neoadjuvant setting in these patients is poorly understood, as is the role for thromboprophylaxis during neoadjuvant chemotherapy. A PubMed search was conducted using a combination of terms including; esophageal & gastric cancer, deep venous thrombosis (DVT), VTE, neoadjuvant, chemotherapy and chemoradiotherapy. One hundred and fifty-four articles were retrieved and a narrative review was conducted. For patients with esophageal and gastric cancer the incidence of VTE ranged from 4 to 19%. Gastric cancer (Odds Ratio [OR] 6.38, [95% CI: 1.96-20.80]) and Stage III/IV disease, (OR 5.16 [95% CI: 1.29-20.73]) were identified as risk factors for developing VTE. Neoadjuvant chemotherapy was identified as an independent risk factor for developing VTE. Symptomatic and asymptomatic VTE have a similar effect on mortality. Median overall survival for asymptomatic VTE was 13.9 months (95% CI: 5.0-∞) versus 12.8 months (95% CI: 4.7-30.3) if the VTE was symptomatic. Neoadjuvant chemotherapy is a significant risk factor for VTE in patients with esophageal and gastric cancer. Intervention to minimize the risk using pharmacological and mechanical thromboprophylaxis should be considered, and this should start in the neoadjuvant period.
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A new silicon tracker for proton imaging and dosimetry. NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH. SECTION A, ACCELERATORS, SPECTROMETERS, DETECTORS AND ASSOCIATED EQUIPMENT 2016; 831:362-366. [PMID: 27667884 PMCID: PMC5002944 DOI: 10.1016/j.nima.2016.02.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
For many years, silicon micro-strip detectors have been successfully used as tracking detectors for particle and nuclear physics experiments. A new application of this technology is to the field of particle therapy where radiotherapy is carried out by use of charged particles such as protons or carbon ions. Such a treatment has been shown to have advantages over standard x-ray radiotherapy and as a result of this, many new centres offering particle therapy are currently under construction around the world today. The Proton Radiotherapy, Verification and Dosimetry Applications (PRaVDA) consortium are developing instrumentation for particle therapy based upon technology from high-energy physics. The characteristics of a new silicon micro-strip tracker for particle therapy will be presented. The array uses specifically designed, large area sensors with technology choices that follow closely those taken for the ATLAS experiment at the HL-LHC. These detectors will be arranged into four units each with three layers in an x-u-v configuration to be suitable for fast proton tracking with minimal ambiguities. The sensors will form a tracker capable of tracing the path of ~200 MeV protons entering and exiting a patient allowing a new mode of imaging known as proton computed tomography (pCT). This will aid the accurate delivery of treatment doses and in addition, the tracker will also be used to monitor the beam profile and total dose delivered during the high fluences used for treatment. We present here details of the design, construction and assembly of one of the four units that will make up the complete tracker along with its characterisation using radiation tests carried out using a 90Sr source in the laboratory and a 60 MeV proton beam at the Clatterbridge Cancer Centre.
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O-015 Association between depth of response (DpR) and survival outcomes in RAS-wild-type (wt) patients with metastatic colorectal cancer (mCRC) receiving first-line FOLFOX or FOLFIRI plus cetuximab once-every-2-weeks in the APEC study. Ann Oncol 2016. [DOI: 10.1093/annonc/mdw198.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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722 Soft tissue mineralization in the Abcc6 -/- mouse: A model for burn-induced heterotopic ossification. J Invest Dermatol 2016. [DOI: 10.1016/j.jid.2016.02.765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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34
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(278) A potential role for eIF4A in regulation of nociceptor plasticity: a motif-based genome-wide search for eIF4A targets. THE JOURNAL OF PAIN 2016. [DOI: 10.1016/j.jpain.2016.01.184] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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35
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'Shrink' losses in commercially sized corn silage piles: Quantifying total losses and where they occur. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 542:530-539. [PMID: 26524271 DOI: 10.1016/j.scitotenv.2015.10.090] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 09/22/2015] [Accepted: 10/19/2015] [Indexed: 06/05/2023]
Abstract
Silage 'shrink' (i.e., loss of fresh chopped crop between ensiling and feedout) represents a nutrient loss which can degrade air quality as volatile carbon compounds, degrade surface waterways due to seepage, or degrade aquifers due to seepage. Virtually no research has documented shrink in large silage piles. The term 'shrink' is often ill defined, but can be expressed as losses of wet weight (WW), oven dry matter (oDM), and oDM corrected for volatiles lost in the drying oven (vcoDM). Corn silage piles (4 wedge, 2 rollover/wedge, 1 bunker) from 950 to 12,204 tonnes as built, on concrete (4), soil (2) and a combination (1) in California's San Joaquin Valley, using a bacterial inoculant, covered within 24 h with an oxygen barrier inner film and black/white outer plastic, fed out using large front end loaders through an electronic feed tracking system, and from the 2013 crop year, were used. Shrink as WW, oDM and vcoDM were 90±17, 68±18 and 28±21 g/kg, suggesting that much WW shrink is water and much oDM shrink is volatiles lost during analytical oven drying. Most shrink occurred in the silage mass with losses from exposed silage faces, as well as between exposed face silage removal and the total mixed ration mixer, being low. Silage bulk density, exposed silage face management and face use rate did not have obvious impacts on any shrink measure, but age of the silage pile during silage feedout impacted shrink losses ('older' silage piles being higher), but most strongly for WW shrink. Real shrink losses (i.e., vcoDM) of large well managed corn silage piles are low, the exposed silage face is a small portion of losses, and many proposed shrink mitigations appeared ineffective, possibly because shrink was low overall and they are largely directed at the exposed silage face.
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Therapeutic hypothermia in cardiac arrest survivors: is rebound hyperthermia a significant issue with intravascular cooling? Intensive Care Med Exp 2015. [PMCID: PMC4797575 DOI: 10.1186/2197-425x-3-s1-a201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
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37
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MRI rectal cancer in Australia and New Zealand: an audit from the PETACC-6 trial. Cancer Imaging 2015. [PMCID: PMC4601852 DOI: 10.1186/1470-7330-15-s1-p44] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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38
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2163 BRAF testing in the community setting; are we testing enough given the importance of BRAF mutation and the clinical implications? Eur J Cancer 2015. [DOI: 10.1016/s0959-8049(16)31083-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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39
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32LBA The AGITG ICECREAM Study: The Irinotecan Cetuximab Evaluation and Cetuximab Response Evaluation Amongst Patients with a G13D Mutation – analysis of outcomes in patients with refractory metastatic colorectal cancer harbouring the KRAS G13D mutation. Eur J Cancer 2015. [DOI: 10.1016/s0959-8049(15)30078-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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2241 Outcome of peptide receptor radionuclide therapy with 177Luoctreotate in advanced neuroendocrine tumours (NET): South Australian sub study of the SIGNETURe Registry. Eur J Cancer 2015. [DOI: 10.1016/s0959-8049(16)31157-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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41
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Phase 1 clinical trial of marizomib (MRZ, NPI-0052) in patients with advanced malignancies including multiple myeloma: study NPI-0052-102 (NCT00629473) final results. CLINICAL LYMPHOMA MYELOMA & LEUKEMIA 2015. [DOI: 10.1016/j.clml.2015.07.563] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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42
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CMOS Active Pixel Sensors as energy-range detectors for proton Computed Tomography. JOURNAL OF INSTRUMENTATION : AN IOP AND SISSA JOURNAL 2015; 10:C06001. [PMID: 29225666 PMCID: PMC5718318 DOI: 10.1088/1748-0221/10/06/c06001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Since the first proof of concept in the early 70s, a number of technologies has been proposed to perform proton CT (pCT), as a means of mapping tissue stopping power for accurate treatment planning in proton therapy. Previous prototypes of energy-range detectors for pCT have been mainly based on the use of scintillator-based calorimeters, to measure proton residual energy after passing through the patient. However, such an approach is limited by the need for only a single proton passing through the energy-range detector in a read-out cycle. A novel approach to this problem could be the use of pixelated detectors, where the independent read-out of each pixel allows to measure simultaneously the residual energy of a number of protons in the same read-out cycle, facilitating a faster and more efficient pCT scan. This paper investigates the suitability of CMOS Active Pixel Sensors (APSs) to track individual protons as they go through a number of CMOS layers, forming an energy-range telescope. Measurements performed at the iThemba Laboratories will be presented and analysed in terms of correlation, to confirm capability of proton tracking for CMOS APSs.
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Proton tracking for medical imaging and dosimetry. JOURNAL OF INSTRUMENTATION : AN IOP AND SISSA JOURNAL 2015; 10:C02015. [PMID: 29367858 PMCID: PMC5777586 DOI: 10.1088/1748-0221/10/02/c02015] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
For many years, silicon micro-strip detectors have been successfully used as tracking detectors for particle and nuclear physics experiments. A new application of this technology is to the field of particle therapy, where radiotherapy is carried out by use of charged particles such as protons or carbon ions. Such a treatment has been shown to have advantages over standard x-ray radiotherapy and as a result of this, many new centres offering particle therapy are currently under construction - including two in the U.K.. The characteristics of a new silicon micro-strip detector based system for this application will be presented. The array uses specifically designed large area sensors in several stations in an x-u-v co-ordinate configuration suitable for very fast proton tracking with minimal ambiguities. The sensors will form a tracker capable of giving information on the path of high energy protons entering and exiting a patient. This will allow proton computed tomography (pCT) to aid the accurate delivery of treatment dose with tuned beam profile and energy. The tracker will also be capable of proton counting and position measurement at the higher fluences and full range of energies used during treatment allowing monitoring of the beam profile and total dose. Results and initial characterisation of sensors will be presented along with details of the proposed readout electronics. Radiation tests and studies with different electronics at the Clatterbridge Cancer Centre and the higher energy proton therapy facility of iThemba LABS in South Africa will also be shown.
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Impact of Baseline Covariates and Prior Therapy on the Efficacy of Second-Line Panitumumab (Pmab) + Folfiri Vs Folfiri Treatment. Ann Oncol 2014. [DOI: 10.1093/annonc/mdu333.50] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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P18.09 * STRESS INDUCED IMMUNE DYSFUNCTION IN NEURO-ONCOLOGY CAREGIVERS. Neuro Oncol 2014. [DOI: 10.1093/neuonc/nou174.433] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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46
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Awake oral fibre-optic intubation in patients with Klippel-Feil syndrome. Int J Obstet Anesth 2014; 23:288-9. [PMID: 24910354 DOI: 10.1016/j.ijoa.2014.03.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Revised: 03/05/2014] [Accepted: 03/15/2014] [Indexed: 11/17/2022]
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Cetuximab Every 2 Weeks with First-Line Chemotherapy in APEC Study Patients with Metastatic Colorectal Cancer Grouped According to EGFR Expression. Ann Oncol 2014. [DOI: 10.1093/annonc/mdu164.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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48
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KRAS/NRAS and BRAF Mutations in the 20050181 Study of Panitumumab + FOLFIRI for the 2ND-Line Treatment of Metastatic Colorectal Cancer: Updated Analysis. Ann Oncol 2014. [DOI: 10.1093/annonc/mdu164.2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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49
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Frequency of S492R Mutations in the Epidermal Growth Factor Receptor: Analysis of Plasma Dna from Metastatic Colorectal Cancer Patients Treated with Panitumumab or Cetuximab Monotherapy. Ann Oncol 2014. [DOI: 10.1093/annonc/mdu193.11] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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50
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Proton-counting radiography for proton therapy: a proof of principle using CMOS APS technology. Phys Med Biol 2014; 59:2569-81. [PMID: 24785680 DOI: 10.1088/0031-9155/59/11/2569] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Despite the early recognition of the potential of proton imaging to assist proton therapy (Cormack 1963 J. Appl. Phys. 34 2722), the modality is still removed from clinical practice, with various approaches in development. For proton-counting radiography applications such as computed tomography (CT), the water-equivalent-path-length that each proton has travelled through an imaged object must be inferred. Typically, scintillator-based technology has been used in various energy/range telescope designs. Here we propose a very different alternative of using radiation-hard CMOS active pixel sensor technology. The ability of such a sensor to resolve the passage of individual protons in a therapy beam has not been previously shown. Here, such capability is demonstrated using a 36 MeV cyclotron beam (University of Birmingham Cyclotron, Birmingham, UK) and a 200 MeV clinical radiotherapy beam (iThemba LABS, Cape Town, SA). The feasibility of tracking individual protons through multiple CMOS layers is also demonstrated using a two-layer stack of sensors. The chief advantages of this solution are the spatial discrimination of events intrinsic to pixelated sensors, combined with the potential provision of information on both the range and residual energy of a proton. The challenges in developing a practical system are discussed.
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