75 results on '"Jonathan Pham"'
Search Results
2. NREM Parasomnias: Retrospective Analysis of Treatment Approaches and Comorbidities
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Naina Limbekar, Jonathan Pham, Rohit Budhiraja, Sogol Javaheri, Lawrence J. Epstein, Salma Batool-Anwar, and Milena Pavlova
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NREM ,parasomnias ,confusional arousals ,sleep walking ,melatonin ,benzodiazepines ,Medicine - Abstract
The aim of this retrospective analysis is to determine the most frequently prescribed medications for the treatment of NREM parasomnias and evaluate reported outcomes. We performed a retrospective chart review of all patients with NREM parasomnia diagnosed within Brigham and Women’s Hospital (BWH) clinics examining the date of diagnosis, date of starting therapy, comorbidities, type of medication prescribed, and the reported change in symptoms or side effects at follow-up visits. From 2012 to 2019, 110 patients (59 females, 51 male) at BWH clinics received a diagnosis of NREM parasomnia, including sleepwalking and night terrors. The mean age was 44. Comorbidities included obstructive sleep apnea (OSA) (46%), periodic limb movement syndrome (PLMS) (13%), insomnia (19%), Restless leg syndrome (RLS) (9%), epilepsy (4%), and REM behavior disorder (RBD) (9%). Initial treatment strategies include behavioral and safety counseling only (34%), pharmacological treatment (29%), treatment of any comorbidity (28%), and combined treatment of any of the above (9%). Improvement was reported with: treatment of OSA (n = 23 52% reported improvement), melatonin (n = 8, improvement reported by 88%.,benzodiazepine (n = 7, improvement reported by 57%). Treating comorbid conditions is a frequent treatment strategy, often associated with symptom improvement. The pharmacologic treatment most commonly included melatonin and benzodiazepines. Comprehensive management should include behavioral and safety recommendations, assessment of comorbid conditions, and individually tailored pharmaceutical treatment.
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- 2022
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3. Impact of the Canadian CT head rule supplemented by the original published minimum inclusion criteria to assist emergency department clinicians’ assessment of patients presenting post fall from residential aged care: a retrospective audit
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Charlene Lee, Jonathan Beavers, Jonathan Pham, Liam Hackett, Joseph Miller, and Paul Buntine
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Computed tomography ,Brain ,Emergency ,Decision support techniques ,Clinical score ,Residential aged care ,Geriatrics ,RC952-954.6 - Abstract
Abstract Background A large number of CT brain (CTB) scans are ordered in the ED for older patients with a confirmed or possible head strike but no ongoing symptoms of a head injury. This study aimed to evaluate the effect of the Canadian CT head rule supplemented by the original published minimum inclusion criteria to assist clinician assessment of the need for CTB following minimal trauma fall in patients presenting from residential aged care facilities to a major metropolitan emergency department (ED). Methods This study was conducted as a pre- and post-intervention retrospective audit. The intervention involved implementation of a decision support tool to help clinicians assess patients presenting to the ED following a fall. The tool integrated the Canadian CT Head Rule (CCHR) in conjunction with a simplified set of inclusion criteria to help clinicians define a minimum threshold for a “minor head injury”. Outcome data pertaining to CT brain ordering practices and results were compared over symmetrical 3-month time periods pre- and post-intervention in 2 consecutive years. Results The study included 233 patients in the pre-intervention arm and 241 in the post-intervention arm. Baseline demographics and clinical characteristics were similar in both groups. There was a 20% reduction in the total number of CTB scans ordered following tool implementation, with 134 (57.0%) scans in the pre-intervention group and 90 (37.3%) in the post-intervention group (p
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- 2022
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4. Framework for patient-specific simulation of hemodynamics in heart failure with counterpulsation support
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Mattia Arduini, Jonathan Pham, Alison L. Marsden, Ian Y. Chen, Daniel B. Ennis, and Seraina A. Dual
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HF ,patient-specific ,hemodynamics ,lumped parameter ,counterpulsation ,McKibben ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Despite being responsible for half of heart failure-related hospitalizations, heart failure with preserved ejection fraction (HFpEF) has limited evidence-based treatment options. Currently, a substantial clinical issue is that the disease etiology is very heterogenous with no patient-specific treatment options. Modeling can provide a framework for evaluating alternative treatment strategies. Counterpulsation strategies have the capacity to improve left ventricular diastolic filling by reducing systolic blood pressure and augmenting the diastolic pressure that drives coronary perfusion. Here, we propose a framework for testing the effectiveness of a soft robotic extra-aortic counterpulsation strategy using a patient-specific closed-loop hemodynamic lumped parameter model of a patient with HFpEF. The soft robotic device prototype was characterized experimentally in a physiologically pressurized (50–150 mmHg) soft silicone vessel and modeled as a combination of a pressure source and a capacitance. The patient-specific model was created using open-source software and validated against hemodynamics obtained by imaging of a patient (male, 87 years, HR = 60 bpm) with HFpEF. The impact of actuation timing on the flows and pressures as well as systolic function was analyzed. Good agreement between the patient-specific model and patient data was achieved with relative errors below 5% in all categories except for the diastolic aortic root pressure and the end systolic volume. The most effective reduction in systolic pressure compared to baseline (147 vs. 141 mmHg) was achieved when actuating 350 ms before systole. In this case, flow splits were preserved, and cardiac output was increased (5.17 vs. 5.34 L/min), resulting in increased blood flow to the coronaries (0.15 vs. 0.16 L/min). Both arterial elastance (0.77 vs. 0.74 mmHg/mL) and stroke work (11.8 vs. 10.6 kJ) were decreased compared to baseline, however left atrial pressure increased (11.2 vs. 11.5 mmHg). A higher actuation pressure is associated with higher systolic pressure reduction and slightly higher coronary flow. The soft robotic device prototype achieves reduced systolic pressure, reduced stroke work, slightly increased coronary perfusion, but increased left atrial pressures in HFpEF patients. In future work, the framework could include additional physiological mechanisms, a larger patient cohort with HFpEF, and testing against clinically used devices.
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- 2022
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5. Elucidating tricuspid Doppler signal interpolation and its implication for assessing pulmonary hypertension
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Seraina A. Dual, Constance Verdonk, Myriam Amsallem, Jonathan Pham, Courtney Obasohan, Patrick Nataf, Doff B. McElhinney, Alisa Arunamata, Tatiana Kuznetsova, Roham Zamanian, Jeffrey A. Feinstein, Alison Marsden, and François Haddad
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echocardiography ,hemodynamics ,pulmonary hypertension ,right heart catheterization ,tricuspid regurgitation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 ,Diseases of the respiratory system ,RC705-779 - Abstract
Abstract Doppler echocardiography plays a central role in the assessment of pulmonary hypertension (PAH). We aim to improve quality assessment of systolic pulmonary arterial pressure (SPAP) by applying a cubic polynomial interpolation to digitized tricuspid regurgitation (TR) waveforms. Patients with PAH and advanced lung disease were divided into three cohorts: a derivation cohort (n = 44), a validation cohort (n = 71), an outlier cohort (n = 26), and a non‐PAH cohort (n = 44). We digitized TR waveforms and analyzed normalized duration, skewness, kurtosis, and first and second derivatives of pressure. Cubic polynomial interpolation was applied to three physiology‐driven phases: the isovolumic phase, ejection phase, and “shoulder” point phase. Coefficients of determination and a Bland−Altman analysis was used to assess bias between methods. The cubic polynomial interpolation of the TR waveform correlated strongly with expert read right ventricular systolic pressure (RVSP) with R2 > 0.910 in the validation cohort. The biases when compared to invasive SPAP measured within 24 h were 6.03 [4.33; 7.73], −2.94 [1.47; 4.41], and −3.11 [−4.52; −1.71] mmHg, for isovolumic, ejection, and shoulder point interpolations, respectively. In the outlier cohort with more than 30% difference between echocardiographic estimates and invasive SPAP, cubic polynomial interpolation significantly reduced underestimation of RVSP. Cubic polynomial interpolation of the TR waveform based on isovolumic or early ejection phase may improve RVSP estimates.
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- 2022
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6. Urethral Interfractional Geometric and Dosimetric Variations of Prostate Cancer Patients: A Study Using an Onboard MRI
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Jonathan Pham, Ricky R. Savjani, Stephanie M. Yoon, Tiffany Yang, Yu Gao, Minsong Cao, Peng Hu, Ke Sheng, Daniel A. Low, Michael Steinberg, Amar U. Kishan, and Yingli Yang
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MR-guided radiation therapy (MRgRT) ,prostate cancer ,dosimetry ,toxicity ,urethra ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
PurposeFor a cohort of prostate cancer patients treated on an MR-guided radiotherapy (MRgRT) system, we retrospectively analyzed urethral interfractional geometric and dosimetric variations based on onboard MRIs acquired at different timepoints and evaluated onboard prostatic urethra visualization for urethra-focused online adaptive RT.MethodsTwenty-six prostate cancer patients were prospectively scanned on a 0.35-T MRgRT system using an optimized T2-weighted HASTE sequence at simulation and final fraction. Two radiation oncologists (RO1 and RO2) contoured the urethras on all HASTE images. The simulation and final fraction HASTE images were rigidly registered, and urethral interobserver and interfractional geometric variation was evaluated using the 95th percentile Hausdorff distance (HD95), mean distance to agreement (MDA), center-of-mass shift (COMS), and DICE coefficient. For dosimetric analysis, simulation and final fraction HASTE images were registered to the 3D bSSFP planning MRI and 3D bSSFP final setup MRI, respectively. Both ROs’ urethra contours were transferred from HASTE images for initial treatment plan optimization and final fraction dose estimation separately. Stereotactic body radiotherapy (SBRT) plans, 40 Gy in 5 fractions, were optimized to meet clinical constraints, including urethral V42Gy ≤0.03 cc, on the planning MRI. The initial plan was then forward calculated on the final setup MRI to estimate urethral dose on the final fraction and evaluate urethral dosimetric impact due to anatomy change.ResultsThe average interobserver HD95, MDA, COMS, and DICE were 2.85 ± 1.34 mm, 1.02 ± 0.36 mm, 3.16 ± 1.61 mm, and 0.58 ± 0.15, respectively. The average interfractional HD95, MDA, COMS, and DICE were 3.26 ± 1.54 mm, 1.29 ± 0.54 mm, 3.34 ± 2.01 mm, and 0.49 ± 0.18, respectively. All patient simulation MRgRT plans met all clinical constraints. For RO1 and RO2, 23/26 (88%) and 21/26 (81%) patients’ final fraction estimated urethral dose did not meet the planned constraint. The average urethral V42Gy change was 0.48 ± 0.58 cc.ConclusionUrethral interfractional motion and anatomic change can result in daily treatment violating urethral constraints. Onboard MRI with good visualization of the prostatic urethra can be a valuable tool to help better protect the urethra through patient setup or online adaptive RT.
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- 2022
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7. Incidence and Distribution of New Renal Cell Carcinoma Cases: 27-Year Trends from a Statewide Cancer Registry
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Ahmad N. Alzubaidi, Stephen Sekoulopoulos, Jonathan Pham, Vonn Walter, Jay G. Fuletra, and Jay D. Raman
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diagnosis ,kidney cancer ,renal cell carcinoma ,statewide ,Diseases of the genitourinary system. Urology ,RC870-923 ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Nationwide databases have implicated an increased incidence of renal cell carcinoma (RCC). The Pennsylvania (PA) Cancer Registry was queried to better define incidence, geographic distribution, and statewide trends of new RCC cases over a 27-year period. JoinPoint Trend Analysis Software modeled average annual percent changes (APCs) in age-adjusted rates (AAR). Maps plotting county-level incidence rates and stage distribution of disease across the state in 5-year time intervals were created using R 4.0.2 software. Overall, 59,628 cases of RCC were recorded in PA from 1990 to 2017. Eighty six percent of patients were >50 years of age, 61% were males, and 89% were Caucasian. Stage distribution using the SEER staging system included 64% local, 17% regional, and 16% distant. Over the study interval, AAR of all RCC cases increased from 9.9 to 18.0 patients per 100,000 population with an APC of 2.3% (p < 0.01). AAR of local disease increased from 5.4 to 12.7 patients per 100,000 population with an APC of 3.2% (p < 0.01). AAR of regional disease also increased from 1.9 to 2.9 patients per 100,000 population with an APC of 1.0% (p = 0.01). Younger patients (
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- 2022
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8. Excess mortality and undertreatment in elderly lung cancer patients: treatment nihilism in the modern era?
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Jonathan Pham, Matthew Conron, Gavin Wright, Paul Mitchell, David Ball, Jennifer Philip, Margaret Brand, John Zalcberg, and Rob G. Stirling
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Medicine - Abstract
Treatment of elderly patients with lung cancer is significantly hindered by concerns about treatment tolerability, toxicity and limited clinical trial data in the elderly; potentially giving rise to treatment nihilism amongst clinicians. This study aims to describe survival in elderly patients with lung cancer and explore potential causes for excess mortality. Patients diagnosed with lung cancer in the Victorian Lung Cancer Registry between 2011–2018 were analysed (n=3481). Patients were age-categorised and compared using Cox-regression modelling to determine mortality risk, after adjusting for confounding. Probability of being offered cancer treatments was also determined, further stratified by disease stage. The eldest patients (≥80 years old) had significantly shorter median survival compared with younger age groups (
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- 2021
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9. Metabolic Functions of G Protein-Coupled Receptors in Hepatocytes—Potential Applications for Diabetes and NAFLD
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Takefumi Kimura, Sai P. Pydi, Jonathan Pham, and Naoki Tanaka
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G protein-coupled receptor ,GPCR ,hepatocyte ,liver ,metabolism ,diabetes ,Microbiology ,QR1-502 - Abstract
G protein-coupled receptors (GPCRs) are cell surface receptors that mediate the function of extracellular ligands. Understanding how GPCRs work at the molecular level has important therapeutic implications, as 30–40% of the drugs currently in clinical use mediate therapeutic effects by acting on GPCRs. Like many other cell types, liver function is regulated by GPCRs. More than 50 different GPCRs are predicted to be expressed in the mouse liver. However, knowledge of how GPCRs regulate liver metabolism is limited. A better understanding of the metabolic role of GPCRs in hepatocytes, the dominant constituent cells of the liver, could lead to the development of novel drugs that are clinically useful for the treatment of various metabolic diseases, including type 2 diabetes, nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH). In this review, we describe the functions of multiple GPCRs expressed in hepatocytes and their role in metabolic processes.
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- 2020
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10. APP knockout mice experience acute mortality as the result of ischemia.
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Maya A Koike, Alexander J Lin, Jonathan Pham, Elaine Nguyen, James J Yeh, Rombod Rahimian, Bruce J Tromberg, Bernard Choi, Kim N Green, and Frank M LaFerla
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Medicine ,Science - Abstract
The incidence of Alzheimer's disease increases in people who have had an ischemic episode. Furthermore, APP expression is increased following ischemic or hypoxic conditions, as is the production of the Aβ peptide. To address the question of why APP and Aβ are increased in hypoxic and ischemic conditions we induced an ischemic episode in APP knockout mice (APP-/-) and BACE1 knockout mice (BACE-/-). We find that both APP-/- and BACE-/- mice have a dramatically increased risk of mortality as a result of cerebral ischemia. Furthermore, APP knockout mice have reduced cerebral blood flow in response to hypoxia, while wild-type mice maintain or increase cerebral blood flow to the same conditions. The transcription factor, serum response factor (SRF), and calcium-binding molecule, calsequestrin, both involved in vascular regulation, are significantly altered in the brains of APP-/- mice compared to wild type controls. These results show that APP regulates cerebral blood flow in response to hypoxia, and that it, and its cleavage fragments, are crucial for rapid adaptation to ischemic conditions.
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- 2012
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11. Urothelium-specific expression of mutationally activatedPik3cainitiates early lesions of non-invasive bladder cancer
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Lauren Shuman, Jonathan Pham, Thomas Wildermuth, Xue-Ru Wu, Vonn Walter, Joshua I. Warrick, and David J. DeGraff
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Despite the fact that ∼70% of bladder cancers are non-invasive and have high recurrence rates, early stage disease is understudied. The relative lack of models to validate the contribution of molecular drivers of bladder tumorigenesis is a significant issue. While mutations inPIK3CAare frequent in human bladder cancer, anin vivomodel for understanding their contribution to bladder tumorigenesis is unavailable. Therefore, aUpk2-Cre/Pik3caH1047Rmouse model expressing one or twoR26-Pik3caH1047Ralleles in a urothelium-specific manner was created.Pik3caH1047Rfunctionality was confirmed by quantifying Akt phosphorylation and mice were characterized by assessing urothelial thickness, nuclear atypia, and expression of luminal and basal markers at 6 and 12 months of age. At 6 months,Pik3caH1047Rmice developed increased urothelial thickness and nuclear atypia, however, at 12 months,Pik3caH1047Rmice did not exhibit progressive disease. Immunohistochemistry shows urothelium maintained luminal differentiation characterized by high Foxa1 and Pparγ expression. In addition, mice were subjected to low-dose carcinogen exposure (N-Butyl-N-(4-hydroxybutyl)nitrosamine (BBN)). Surprisingly,Pik3caH1047Rmice exhibited no significant differences after exposure relative to mice without exposure. Furthermore, ssGSEA analysis of invasive human tumors showed those with mutantPIK3CAdo not exhibit significantly increased PI3K/AKT pathway activity compared to wildtypePIK3CAtumors. Overall, these data suggest thatPik3caH1047Rcan elicit early tumorigenic changes in the urothelium, but progression to invasion may require additional genetic alterations.
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- 2023
12. Longitudinal Asthma Phenotypes from Childhood to Middle-Age: A Population-based Cohort Study
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Daniel J Tan, Caroline J Lodge, E. Haydn Walters, Adrian J. Lowe, Dinh S. Bui, Gayan Bowatte, Jonathan Pham, Bircan Erbas, Jennie Hui, Garun S Hamilton, Paul S Thomas, Mark Hew, George Washko, Richard Wood-Baker, Michael J Abramson, Jennifer L Perret, and Shyamali C. Dharmage
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Pulmonary and Respiratory Medicine ,Critical Care and Intensive Care Medicine - Published
- 2023
13. Genetic ancestry is associated with asthma, and this could be modified by environmental factors. A systematic review
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Jonathan Pham, Dinh S. Bui, Caroline J. Lodge, Michael J. Abramson, Adrian J. Lowe, Shuai Li, Aung K. Win, Mark Hew, and Shyamali C. Dharmage
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Immunology ,Immunology and Allergy - Published
- 2023
14. MP75-09 RURAL AND URBAN GENITOURINARY CANCER INCIDENCE AND MORTALITY IN THE PENNSYLVANIA CANCER REGISTRY FROM 1990-2019
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Jonathan Pham, Ahmad Alzubaidi, Tullika Garg, and Jay Raman
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Urology - Published
- 2023
15. MP69-11 PREDICTIVE NOMOGRAM FOR POST-NEPHROURETERECTOMY GFR ESTIMATION
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Patrick Hensley, Craig Labbate, Lianchun Xiao, Andrew Zganjar, Trey Durdin, Heather Huelster, Jonathan Pham, Jeffrey Howard, Maximilian Pallauf, Kara Lombardo, Aaron Potretzke, Philippe Spiess, Jay Raman, Vitaly Margulis, Nirmish Singla, Jonathan Coleman, and Surena Matin
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Urology - Published
- 2023
16. Trait profiles in difficult‐to‐treat asthma: Clinical impact and response to systematic assessment
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Tiffany Lin, Jonathan Pham, Eve Denton, Joy Lee, Fiona Hore‐Lacy, Asger Sverrild, Stephanie Stojanovic, Tunn Ren Tay, Kavitha Garuna Murthee, Naghmeh Radhakrishna, Monique Dols, Janet Bondarenko, Janine Mahoney, Robyn E. O'Hehir, Eli Dabscheck, and Mark Hew
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Immunology ,Immunology and Allergy - Published
- 2023
17. 2‐Step PLT16‐AST44 method: Simplified liver fibrosis detection system in patients with non‐alcoholic fatty liver disease
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Naoyuki Fujimori, Takefumi Kimura, Naoki Tanaka, Tomoo Yamazaki, Taiki Okumura, Hiroyuki Kobayashi, Shun‐ichi Wakabayashi, Yuki Yamashita, Ayumi Sugiura, Jonathan Pham, Sai P. Pydi, Kenji Sano, Satoru Joshita, and Takeji Umemura
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Infectious Diseases ,Hepatology - Abstract
Accurate detection of the hepatic fibrosis stage is essential to estimate the outcome of patients with non-alcoholic fatty liver disease (NAFLD). Many formulas, biomarkers, and imaging tests are being developed to predict advanced liver fibrosis without performing a liver biopsy. However, these tests do not have high efficiency in detecting early-stage hepatic fibrosis. Therefore, we aimed to detect the presence of hepatic fibrosis (≥F1) merely by using only standard clinical markers.A total of 436 patients with NAFLD who underwent liver biopsy were retrospectively enrolled as the discovery cohort (316 patients) and the validation cohort (120 patients). Liver biopsy and laboratory data were matched to extract simple parameters for identifying ≥F1.We developed a novel simplified ≥F1 detecting system, designated as 2-Step PLT16-AST44 method, where (1) PLT of 16 × 10We propose the 2-Step PLT16-AST44 method as a simple and beneficial early-stage hepatic fibrosis detection system.
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- 2022
18. Recent Advances in Functional MRI to Predict Treatment Response for Locally Advanced Rectal Cancer
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Yingli Yang, Yu Gao, Stephanie M. Yoon, Minsong Cao, Peng Hu, and Jonathan Pham
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Treatment response ,medicine.medical_specialty ,Hepatology ,Colorectal cancer ,business.industry ,Gastroenterology ,Locally advanced ,Small sample ,medicine.disease ,Treatment management ,Oncology ,Radiomics ,medicine ,Biomarker (medicine) ,In patient ,Medical physics ,business - Abstract
Early response prediction for locally advanced rectal cancer (LARC) provides an opportunity for response-tailored treatment management. The goal of this review is to summarize recent advances in applying functional MRI, such as diffusion-weighted imaging (DWI) and dynamic contrast-enhanced MRI (DCE-MRI), to predict treatment response for LARC patients, as well as to discuss the associated limitations and future directions. Many recent studies incorporated advanced data analysis methods, such as radiomics and deep learning, to enhance prediction performance. Multi-parametric imaging has also become a trend that utilizes complementary information from each technique. However, there are wide variations in patient enrollment, imaging time points, scan parameters, and treatment response endpoint definitions, which leads to a range of findings among these studies. Moreover, small sample size and lack of independent validation of most studies also weaken conclusions. Functional MRI has been shown as a potential early biomarker for rectal cancer treatment response estimation. To incorporate functional MRI into clinical workflow, future work with large standardized data are warranted.
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- 2021
19. Impact of Socioeconomic Status on Adult Patients with Asthma: A Population-Based Cohort Study from UK Primary Care
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Désirée Larenas Linnemann, Bassam Mahboub, Eileen Wang, Susanne Hansen, Benjamin Emmanuel, John Busby, Nicolas Roche, Patrick Mitchell, Mark Hew, Celeste Porsbjerg, Takashi Iwanaga, Liam G Heaney, Riyad Al-Lehebi, Job F M van Boven, Mina Gaga, Sinthia Bosnic-Anticevich, Neva Eleangovan, J. Mark FitzGerald, Daniela Morrone, Jonathan Pham, David Price, Groningen Research Institute for Asthma and COPD (GRIAC), Value, Affordability and Sustainability (VALUE), and Real World Studies in PharmacoEpidemiology, -Genetics, -Economics and -Therapy (PEGET)
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Pulmonary and Respiratory Medicine ,Exacerbation ,Ethnic group ,Disparities ,Disease ,socioeconomic status ,Population based cohort ,socioeconomics ,Journal of Asthma and Allergy ,medicine ,Immunology and Allergy ,adherence ,Socioeconomic status ,Asthma ,Original Research ,disparities ,Adult patients ,business.industry ,asthma ,RC581-607 ,medicine.disease ,Socioeconomic Status ,Cohort ,Immunologic diseases. Allergy ,business ,Demography - Abstract
John Busby,1 David Price,2â 4 Riyad Al-Lehebi,5 Sinthia Bosnic-Anticevich,6â 8 Job FM van Boven,9 Benjamin Emmanuel,10 J Mark FitzGerald,11 Mina Gaga,12 Susanne Hansen,13,14 Mark Hew,15,16 Takashi Iwanaga,17 Désirée Larenas Linnemann,18 Bassam Mahboub,19,20 Patrick Mitchell,21 Daniela Morrone,22 Jonathan Pham,15,23 Celeste Porsbjerg,14 Nicolas Roche,24,25 Eileen Wang,26,27 Neva Eleangovan,2,3 Liam G Heaney28 1Centre for Public Health, Queenâs University Belfast, Belfast, Northern Ireland; 2Optimum Patient Care, Cambridge, UK; 3Observational and Pragmatic Research Institute, Singapore, Singapore; 4Centre of Academic Primary Care, Division of Applied Health Sciences, University of Aberdeen, Aberdeen, UK; 5Department of Pulmonology, King Fahad Medical City, Riyadh, Saudi Arabia; 6Sydney Pharmacy School, Faculty of Medicine and Health, The University of Sydney, Sydney, Australia; 7Woolcock Institute of Medical Research, The University of Sydney, Sydney, Australia; 8Central Sydney Local Area Health District, Sydney, Australia; 9Department of Clinical Pharmacy & Pharmacology, Groningen Research Institute for Asthma and COPD (GRIAC), University Medical Center Groningen, University of Groningen, Groningen, the Netherlands; 10BioPharmaceuticals Medical, AstraZeneca, Gaithersburg, MD, USA; 11Department of Medicine, The University of British Columbia, Vancouver, Canada; 12 7th Respiratory Medicine Department and Asthma Centre, Athens Chest Hospital, Athens, Greece; 13Center for Clinical Research and Prevention, Bispebjerg and Frederiksberg Hospital, Copenhagen, Denmark; 14Respiratory Research Unit, Bispebjerg University Hospital, Copenhagen, Denmark; 15Allergy, Asthma & Clinical Immunology Service, Alfred Health, Melbourne, Australia; 16Public Health and Preventive Medicine, Monash University, Melbourne, Australia; 17Center for General Medical Education and Clinical Training, Kindai University Hospital, Osakasayama, Japan; 18Directora Centro de Excelencia en Asma y Alergia, Hospital Médica Sur, Ciudad de México, Mexico; 19College of Medicine, University of Sharjah, Sharjah, United Arab Emirates; 20Rashid Hospital, Dubai Health Authority, Dubai, United Arab Emirates; 21Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada; 22Personalized Medicine, Asthma and Allergy, Humanitas Clinical and Research Center, IRCCS, Rozzano, Italy; 23Allergy and Lung Health Unit, Centre for Epidemiology and Biostatistics, Melbourne School of Population & Global Health, The University of Melbourne, Melbourne, Australia; 24Respiratory Medicine, Cochin Hospital, APHP.Centre, Paris, France; 25University of Paris, Cochin Institute (UMR1016), Paris, France; 26Division of Allergy & Clinical Immunology, Department of Medicine, National Jewish Health, Denver, CO, USA; 27Division of Allergy & Clinical Immunology, Department of Internal Medicine, University of Colorado School of Medicine, Aurora, CO, USA; 28Wellcome-Wolfson Centre for Experimental Medicine, Queenâs University Belfast, Belfast, Northern IrelandCorrespondence: David PriceCentre of Academic Primary Care, Division of Applied Health Sciences, University of Aberdeen, Polwarth Building, Foresterhill, Aberdeen, AB25 2ZD, UKTel +65 6962 3627Email dprice@opri.sgIntroduction: Asthma morbidity and health-care utilization are known to exhibit a steep socioeconomic gradient. Further investigation into the modulators of this effect is required to identify potentially modifiable factors.Methods: We identified a cohort of patients with asthma from the Optimum Patient Care Research Database (OPCRD). We compared demographics, clinical variables, and health-care utilization by quintile of the UK 2011 Indices of Multiple Deprivation based on the location of the patientsâ general practice. Multivariable analyses were conducted using generalized linear models adjusting for year, age, and sex. We conducted subgroup analyses and interaction tests to investigate the impact of deprivation by age, sex, ethnicity, and treatment step.Results: Our analysis included 127,040 patients with asthma. Patients from the most deprived socio-economic status (SES) quintile were more likely to report uncontrolled disease (OR: 1.54, 95% CI: 1.16, 2.05) and to have an exacerbation during follow-up (OR: 1.27, 95% CI: 1.13, 1.42) than the least deprived quintile. They had higher blood eosinophils (ratio: 1.03; 95% CI: 1.00, 1.06) and decreased peak flow (ratio: 0.95, 95% CI: 0.94, 0.97) when compared to those in the least deprived quintile. The effect of deprivation on asthma control was greater among those aged over 75 years (OR = 1.81, 95% CI: 1.20, 2.73) compared to those aged less than 35 years (OR: 1.22, 95% CI: 0.85, 1.74; pinteraction=0.019). Similarly, socioeconomic disparities in exacerbations were larger among those from ethnic minority groups (OR: 1.94, 95% CI: 1.40, 2.68) than white patients (OR: 1.24, 95% CI: 1.10, 1.39; pinteraction=0.012).Conclusion: We found worse disease control and increased exacerbation rates among patients with asthma from more deprived areas. There was evidence that the magnitude of socioeconomic disparities was elevated among older patients and those from ethnic minority groups. The drivers of these differences require further exploration.Keywords: asthma, socioeconomic status, disparities
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- 2021
20. Prevalence and predictors of inappropriate dosing of direct oral anticoagulants
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Hiu T. K. Ko, Jonathan Pham, and Mahesan Anpalahan
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Internal Medicine - Abstract
Information on inappropriate dosing of direct oral anticoagulants (DOACs) is scarce in the Australian context.To describe the prevalence and potential predictors of inappropriate dosing of DOACs.Patients who received DOACs during admission under a general medical unit over a 2-year period (from January 2017 to December 2018) were retrospectively studied. Appropriateness of the dosing regimen was verified against the recommendations of the Therapeutic Goods Administration of Australia. Data were obtained from medical records and analysed in univariate and multivariate logistic regression models. The variables associated with under- and overdosing were also determined.A total of 203 (mean age 71.6 ± 14.5 years, females 52%) patients were studied. Inappropriate dosing occurred in 44 (22%) patients: underdosing 27 (13%) and overdosing 17 (8%). Age ≥75 years (P 0.01), lower estimated creatinine clearance (CrCl) (P 0.01), prescription of DOAC prior to index admission (P 0.01) and higher Charlson Comorbidity Index (P 0.01), HAS-BLED (P 0.01) and CHAInappropriate dosing of DOACs, especially underdosing, is common in clinical practice. Clinicians should exercise due diligence when prescribing DOACs to patients with renal impairment and in outpatient settings.
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- 2022
21. Cover Image
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Martin R. Pfaller, Jonathan Pham, Aekaansh Verma, Luca Pegolotti, Nathan M. Wilson, David W. Parker, Weiguang Yang, and Alison L. Marsden
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Computational Theory and Mathematics ,Applied Mathematics ,Modeling and Simulation ,Biomedical Engineering ,Molecular Biology ,Software - Published
- 2022
22. Excess mortality and undertreatment in elderly lung cancer patients: treatment nihilism in the modern era?
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Matthew Conron, Paul Mitchell, Jennifer Philip, Margaret Brand, Robert G Stirling, John Zalcberg, Gavin M. Wright, Jonathan Pham, and David Ball
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Performance status ,business.industry ,Lung Cancer ,Cancer ,Original Articles ,Disease ,medicine.disease ,Comorbidity ,Clinical trial ,03 medical and health sciences ,0302 clinical medicine ,Tolerability ,030220 oncology & carcinogenesis ,Internal medicine ,Risk of mortality ,medicine ,Medicine ,030212 general & internal medicine ,Lung cancer ,business - Abstract
Treatment of elderly patients with lung cancer is significantly hindered by concerns about treatment tolerability, toxicity and limited clinical trial data in the elderly; potentially giving rise to treatment nihilism amongst clinicians. This study aims to describe survival in elderly patients with lung cancer and explore potential causes for excess mortality. Patients diagnosed with lung cancer in the Victorian Lung Cancer Registry between 2011–2018 were analysed (n=3481). Patients were age-categorised and compared using Cox-regression modelling to determine mortality risk, after adjusting for confounding. Probability of being offered cancer treatments was also determined, further stratified by disease stage. The eldest patients (≥80 years old) had significantly shorter median survival compared with younger age groups (, Treatment strongly determines lung cancer survival, yet nihilism may threaten treatment provision and survival outcomes. Older patients in this cohort had reduced multidisciplinary presentation, less treatment (OR 0.24) and 28% increased mortality risk. https://bit.ly/2ZGotj0
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- 2021
23. Magnetic Resonance Imaging–Guided vs Computed Tomography–Guided Stereotactic Body Radiotherapy for Prostate Cancer
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Amar U. Kishan, Ting Martin Ma, James M. Lamb, Maria Casado, Holly Wilhalme, Daniel A. Low, Ke Sheng, Sahil Sharma, Nicholas G. Nickols, Jonathan Pham, Yingli Yang, Yu Gao, John Neylon, Vincent Basehart, Minsong Cao, and Michael L. Steinberg
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Cancer Research ,Oncology - Abstract
ImportanceMagnetic resonance imaging (MRI) guidance offers multiple theoretical advantages in the context of stereotactic body radiotherapy (SBRT) for prostate cancer. However, to our knowledge, these advantages have yet to be demonstrated in a randomized clinical trial.ObjectiveTo determine whether aggressive margin reduction with MRI guidance significantly reduces acute grade 2 or greater genitourinary (GU) toxic effects after prostate SBRT compared with computed tomography (CT) guidance.Design, Setting, and ParticipantsThis phase 3 randomized clinical trial (MRI-Guided Stereotactic Body Radiotherapy for Prostate Cancer [MIRAGE]) enrolled men aged 18 years or older who were receiving SBRT for clinically localized prostate adenocarcinoma at a single center between May 5, 2020, and October 1, 2021. Data were analyzed from January 15, 2021, through May 15, 2022. All patients had 3 months or more of follow-up.InterventionsPatients were randomized 1:1 to SBRT with CT guidance (control arm) or MRI guidance. Planning margins of 4 mm (CT arm) and 2 mm (MRI arm) were used to deliver 40 Gy in 5 fractions.Main Outcomes and MeasuresThe primary end point was the incidence of acute (≤90 days after SBRT) grade 2 or greater GU toxic effects (using Common Terminology Criteria for Adverse Events, version 4.03 [CTCAE v4.03]). Secondary outcomes included CTCAE v4.03–based gastrointestinal toxic effects and International Prostate Symptom Score (IPSS)–based and Expanded Prostate Cancer Index Composite-26 (EPIC-26)–based outcomes.ResultsBetween May 2020 and October 2021, 156 patients were randomized: 77 to CT (median age, 71 years [IQR, 67-77 years]) and 79 to MRI (median age, 71 years [IQR, 68-75 years]). A prespecified interim futility analysis conducted after 100 patients reached 90 or more days after SBRT was performed October 1, 2021, with the sample size reestimated to 154 patients. Thus, the trial was closed to accrual early. The incidence of acute grade 2 or greater GU toxic effects was significantly lower with MRI vs CT guidance (24.4% [95% CI, 15.4%-35.4%] vs 43.4% [95% CI, 32.1%-55.3%]; P = .01), as was the incidence of acute grade 2 or greater gastrointestinal toxic effects (0.0% [95% CI, 0.0%-4.6%] vs 10.5% [95% CI, 4.7%-19.7%]; P = .003). Magnetic resonance imaging guidance was associated with a significantly smaller percentage of patients with a 15-point or greater increase in IPSS at 1 month (6.8% [5 of 72] vs 19.4% [14 of 74]; P = .01) and a significantly reduced percentage of patients with a clinically significant (≥12-point) decrease in EPIC-26 bowel scores (25.0% [17 of 68] vs 50.0% [34 of 68]; P = .001) at 1 month.Conclusions and RelevanceIn this randomized clinical trial, compared with CT-guidance, MRI-guided SBRT significantly reduced both moderate acute physician-scored toxic effects and decrements in patient-reported quality of life. Longer-term follow-up will confirm whether these notable benefits persist.Trial RegistrationClinicalTrials.gov Identifier: NCT04384770
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- 2023
24. S917 Effectiveness and Safety of Weight Loss Medical Therapy in Ulcerative Colitis
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Jonathan Pham and Amanda Johnson
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Hepatology ,Gastroenterology - Published
- 2022
25. svMorph: Interactive Geometry-Editing Tools for Virtual Patient-Specific Vascular Anatomies
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Jonathan Pham, Sofia Wyetzner, Martin R. Pfaller, David W. Parker, Doug L. James, and Alison L. Marsden
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FOS: Computer and information sciences ,Models, Anatomic ,Biomedical Engineering ,Models, Cardiovascular ,Hemodynamics ,FOS: Physical sciences ,Physics - Medical Physics ,Computational Engineering, Finance, and Science (cs.CE) ,Physiology (medical) ,Hydrodynamics ,Humans ,Computer Simulation ,Medical Physics (physics.med-ph) ,Computer Science - Computational Engineering, Finance, and Science - Abstract
We propose svMorph, a framework for interactive virtual sculpting of patient-specific vascular anatomic models. Our framework includes three tools for the creation of tortuosity, aneurysms, and stenoses in tubular vascular geometries. These shape edits are performed via geometric operations on the surface mesh and vessel centerline curves of the input model. The tortuosity tool also uses the physics-based Oriented Particles method, coupled with linear blend skinning, to achieve smooth, elastic-like deformations. Our tools can be applied separately or in combination to produce simulation-suitable morphed models. They are also compatible with popular vascular modeling software, such as simvascular. To illustrate our tools, we morph several image-based, patient-specific models to create a range of shape changes and simulate the resulting hemodynamics via three-dimensional, computational fluid dynamics. We also demonstrate the ability to quickly estimate the hemodynamic effects of the shape changes via the automated generation of associated zero-dimensional lumped-parameter models.
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- 2022
26. Fully automated segmentation of prostatic urethra for MR-guided radiation therapy
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Di Xu, Ting Martin Ma, Ricky Savjani, Jonathan Pham, Minsong Cao, Yingli Yang, Amar U. Kishan, Fabien Scalzo, and Ke Sheng
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General Medicine - Abstract
Accurate delineation of the urethra is a prerequisite for urethral dose reduction in prostate radiotherapy. However, even in magnetic resonance-guided radiation therapy (MRgRT), consistent delineation of the urethra is challenging, particularly in online adaptive radiotherapy. This paper presented a fully automatic MRgRT-based prostatic urethra segmentation framework.Twenty-eight prostate cancer patients were included in this study. In-house 3D half fourier single-shot turbo spin-echo (HASTE) and turbo spin echo (TSE) sequences were used to image the Foley-free urethra on a 0.35 T MRgRT system. The segmentation pipeline uses 3D nnU-Net as the base and innovatively combines ground truth and its corresponding radial distance (RD) map during training supervision. Additionally, we evaluate the benefit of incorporating a convolutional long short term memory (LSTM-Conv) layer and spatial recurrent convolution layer (RCL) into nnU-Net. A novel slice-by-slice simple exponential smoothing (SEPS) method specifically for tubular structures was used to post-process the segmentation results.The experimental results show that nnU-Net trained using a combination of Dice, cross-entropy and RD achieved a Dice score of 77.1 ± 2.3% in the testing dataset. With SEPS, Hausdorff distance (HD) and 95% HD were reduced to 2.95 ± 0.17 mm and 1.84 ± 0.11 mm, respectively. LSTM-Conv and RCL layers only minimally improved the segmentation precision.We present the first Foley-free MRgRT-based automated urethra segmentation study. Our method is built on a data-driven neural network with novel cost functions and a post-processing step designed for tubular structures. The performance is consistent with the need for online and offline urethra dose reduction in prostate radiotherapy.
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- 2022
27. Impact of the Canadian CT head rule supplemented by the original published minimum inclusion criteria to assist emergency department clinicians' assessment of patients presenting post fall from residential aged care: a retrospective audit
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Charlene Lee, Jonathan Beavers, Jonathan Pham, Liam Hackett, Joseph Miller, and Paul Buntine
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Canada ,Craniocerebral Trauma ,Humans ,Prospective Studies ,Geriatrics and Gerontology ,Emergency Service, Hospital ,Tomography, X-Ray Computed ,Sensitivity and Specificity ,Aged ,Retrospective Studies - Abstract
Background A large number of CT brain (CTB) scans are ordered in the ED for older patients with a confirmed or possible head strike but no ongoing symptoms of a head injury. This study aimed to evaluate the effect of the Canadian CT head rule supplemented by the original published minimum inclusion criteria to assist clinician assessment of the need for CTB following minimal trauma fall in patients presenting from residential aged care facilities to a major metropolitan emergency department (ED). Methods This study was conducted as a pre- and post-intervention retrospective audit. The intervention involved implementation of a decision support tool to help clinicians assess patients presenting to the ED following a fall. The tool integrated the Canadian CT Head Rule (CCHR) in conjunction with a simplified set of inclusion criteria to help clinicians define a minimum threshold for a “minor head injury”. Outcome data pertaining to CT brain ordering practices and results were compared over symmetrical 3-month time periods pre- and post-intervention in 2 consecutive years. Results The study included 233 patients in the pre-intervention arm and 241 in the post-intervention arm. Baseline demographics and clinical characteristics were similar in both groups. There was a 20% reduction in the total number of CTB scans ordered following tool implementation, with 134 (57.0%) scans in the pre-intervention group and 90 (37.3%) in the post-intervention group (p p = 0.52). No variation was observed in medical management between groups, and no patients in either group underwent neurosurgical intervention. Conclusions Use of the CCHR supplemented by the original published minimum inclusion criteria appeared to safely reduce the number of CTB scans performed in residential aged care facility residents presenting to an ED after a fall, with no associated adverse outcomes. A larger study across multiple centres is required to determine widespread efficacy and safety of this tool.
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- 2021
28. Is ethnicity a ‘treatable trait’ in asthma?
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Mark Hew, Shyamali C. Dharmage, and Jonathan Pham
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,business.industry ,Internal medicine ,Ethnic group ,Trait ,Medicine ,business ,medicine.disease ,Asthma - Published
- 2021
29. Abstract 10657: Automated Tracing of Tricuspid Regurgitation Doppler Waveforms
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Jonathan Pham, Seraina A Dual, Constance Verdonk, Myriam Amsallem, Jeffrey A Feinstein, Francois Haddad, and Alison L Marsden
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Physiology (medical) ,Cardiology and Cardiovascular Medicine - Abstract
Introduction: The definition of pulmonary hypertension relies on the invasive measurement of increased pulmonary arterial pressures (PAPs). The systolic PAP can be non-invasively estimated from the maximal velocity (Vmax) of tricuspid regurgitation (TR) Doppler signals. However, the accuracy of this method is conditioned by the quality of the TR signal. It is also subject to high interobserver variability. To address these issues, we developed an automated, machine-learning framework to analyze TR signals. We hypothesize our method can accurately predict Vmax and velocity time integral (VTI) for any TR signal. Methods: We analyzed 306 TR Doppler signals consisting of high and intermediate signal qualities from 65 patients (median 50 [21, 86] years old). Our method combines a U-Net convolutional neural network with OpenCV, an image processing tool. The U-Net performs semantic image segmentation on an input TR Doppler signal. OpenCV then deduces the Vmax and VTI of the curve. We compared our predictions against expert assessments of the TR signal, Vmax, and VTI. We used 230/56 signals for training/validation to determine the optimal parameters in our U-Net and 20 signals for testing to obtain an unbiased measure of performance. Results: As shown in the figure, our framework accurately predicts Vmax with a bias of 0.06 m/s and 95% limits of agreement of [-0.50, 0.63] m/s, and VTI with a bias of 0.01 m and 95% limits of agreement of [-0.22, 0.23] m. Two signals proved difficult to trace due to noisy images. Our framework takes about 5 seconds to predict Vmax and VTI for each TR signal. Conclusions: The accuracy of the predicted Vmax and VTI is heavily influenced by the quality of the input TR signal. We can solve this issue by training our U-Net on a larger dataset and leveraging other computer-vision techniques or flagging these signals for user intervention. Automation of signal analysis opens the door for more detailed curve analysis on larger clinical cohorts.
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- 2021
30. MP45-13 INCIDENCE AND DISTRIBUTION OF NEW RENAL CELL CARCINOMA CASES: 27-YEAR TRENDS FROM A STATEWIDE CANCER REGISTRY
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Jay Fuletra, Jonathan Pham, Suzanne B. Merrill, Ahmad N. Alzubaidi, Jay D. Raman, Matthew Kaag, and Vonn Walter
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Oncology ,medicine.medical_specialty ,business.industry ,Renal cell carcinoma ,Urology ,Incidence (epidemiology) ,Internal medicine ,Medicine ,Distribution (pharmacology) ,urologic and male genital diseases ,business ,medicine.disease ,Cancer registry - Abstract
INTRODUCTION AND OBJECTIVE:Prior studies using nationwide databases have implicated an increased incidence of renal cell carcinoma (RCC) over time. Granular data, however, may highlight potential g...
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- 2021
31. Hydrophobic surface patterning with soft, wax-infused micro-stamps
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Soroosh Torabi, Zhuoyun Cai, Jonathan Pham, and Christine Trinkle
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In this paper, we demonstrate an easy-to-use and inexpensive stamping method that can be used to generate hydrophobic paraffin surface patterns on a variety of materials and surface geometries, including flat and curved surfaces. In this method, a waxy Parafilm sheet is placed on the back of a polydimethylsiloxane (PDMS) stamp containing microscale surface features; when heated above the melting temperature, the paraffin liquefies and diffuses into the stamp, which functions as a paraffin reservoir. The directional diffusion of the paraffin allows only a thin layer of liquid to be present at the micropatterned stamp surface. Hence, when it is put into contact with a target surface, it transfers a paraffin pattern with submicron lateral resolution and sub-100 nm thickness. By using XPS analysis to track paraffin diffusion process within the PDMS stamp, the diffusion coefficient in PDMS is estimated to be 5.3 x 10-11 m2/s at 65°C. In addition to improved patterning, the paraffin-saturated PDMS stamp removes the need for re-inking for consecutive patterning. In general, our process allows for rapid deposition of complex, multi-layer paraffin patterns on a variety of surfaces.
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- 2021
32. Evaluation of T2-Weighted MRI for Visualization and Sparing of Urethra with MR-Guided Radiation Therapy (MRgRT) On-Board MRI
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Yu Gao, Michael L. Steinberg, Peng Hu, Ke Sheng, Ricky R. Savjani, Jonathan Pham, Amar U. Kishan, Minsong Cao, Daniel A. Low, and Yingli Yang
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Urologic Diseases ,Cancer Research ,treatment planning ,medicine.medical_treatment ,Oncology and Carcinogenesis ,Bioengineering ,Article ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,Prostate cancer ,0302 clinical medicine ,Prostatic urethra ,MR-guided radiation therapy (MRgRT) ,Clinical Research ,Medicine ,Radiation treatment planning ,RC254-282 ,Radiation oncologist ,Cancer ,Contouring ,contouring ,Genitourinary system ,business.industry ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,medicine.disease ,prostate cancer ,Radiation therapy ,Urethra ,medicine.anatomical_structure ,MR-guided radiation therapy ,Oncology ,030220 oncology & carcinogenesis ,Biomedical Imaging ,genitourinary (GU) toxicity ,urethra ,business ,Nuclear medicine - Abstract
Simple Summary Stereotactic body radiation therapy (SBRT) has become a standard of care option for prostate cancer patients, utilizing large fractionated dose to shorten treatment times. However, genitourinary (GU) toxicity associated with urethral injury remains prevalent due to non-trivial urethra delineation and sparing at treatment planning and treatment delivery. The aim of our study was to evaluate two optimized urethral MRI sequences (3D HASTE and 3D TSE) with a 0.35T MR-guided radiotherapy (MRgRT) system for urethral visibility and delineation. Among 11 prostate cancer patients, a radiation oncologist qualitatively scored MRgRT 3D HASTE as having the best urethra visibility, superior to CT, clinical MRgRT 3D bSSFP, MRgRT 3D TSE, and similar to diagnostic 3T (2D/3D) T2-weighetd MRI. Moreover, urethra contours from different imaging and clinical workflows demonstrated significant urethra localization variability. Optimized 3D MRgRT HASTE can provide urethral visualization and delineation within an MRgRT workflow for urethral sparing, avoiding cross-modality/system registration errors. Abstract Purpose: To evaluate urethral contours from two optimized urethral MRI sequences with an MR-guided radiotherapy system (MRgRT). Methods: Eleven prostate cancer patients were scanned on a MRgRT system using optimized urethral 3D HASTE and 3D TSE. A resident radiation oncologist contoured the prostatic urethra on the patients’ planning CT, diagnostic 3T T2w MRI, and both urethral MRIs. An attending radiation oncologist reviewed/edited the resident’s contours and additionally contoured the prostatic urethra on the clinical planning MRgRT MRI (bSSFP). For each image, the resident radiation oncologist, attending radiation oncologist, and a senior medical physicist qualitatively scored the prostatic urethra visibility. Using MRgRT 3D HASTE-based contouring workflow as baseline, prostatic urethra contours drawn on CT, diagnostic MRI, clinical bSSFP and 3D TSE were evaluated relative to the contour on 3D HASTE using 95th percentile Hausdorff distance (HD95), mean-distance-to-agreement (MDA), and DICE coefficient. Additionally, prostatic urethra contrast-to-noise-ratios (CNR) were calculated for all images. Results: For two out of three observers, the urethra visibility score for 3D HASTE was significantly higher than CT, and clinical bSSFP, but was not significantly different from diagnostic MRI. The mean HD95/MDA/DICE values were 11.35 ± 3.55 mm/5.77 ± 2.69 mm/0.07 ± 0.08 for CT, 7.62 ± 2.75 mm/3.83 ± 1.47 mm/0.12 ± 0.10 for CT + diagnostic MRI, 5.49 ± 2.32 mm/2.18 ± 1.19 mm/0.35 ± 0.19 for 3D TSE, and 6.34 ± 2.89 mm/2.65 ± 1.31 mm/0.21 ± 0.12 for clinical bSSFP. The CNR for 3D HASTE was significantly higher than CT, diagnostic MRI, and clinical bSSFP, but was not significantly different from 3D TSE. Conclusion: The urethra’s visibility scores showed optimized urethral MRgRT 3D HASTE was superior to the other tested methodologies. The prostatic urethra contours demonstrated significant variability from different imaging and workflows. Urethra contouring uncertainty introduced by cross-modality registration and sub-optimal imaging contrast may lead to significant treatment degradation when urethral sparing is implemented to minimize genitourinary toxicity.
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- 2021
33. On the periodicity of cardiovascular fluid dynamics simulations
- Author
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David Parker, Nathan M. Wilson, Martin R. Pfaller, Alison L. Marsden, and Jonathan Pham
- Subjects
FOS: Computer and information sciences ,Periodicity ,Computer science ,Computation ,Biomedical Engineering ,Initialization ,FOS: Physical sciences ,Article ,Rendering (computer graphics) ,Reduction (complexity) ,Computational Engineering, Finance, and Science (cs.CE) ,Cardiovascular Physiological Phenomena ,Software ,Convergence (routing) ,Fluid dynamics ,Humans ,Computer Science - Computational Engineering, Finance, and Science ,Patient-Specific Modeling ,business.industry ,Hemodynamics ,Models, Cardiovascular ,Physics - Medical Physics ,Hydrodynamics ,Medical Physics (physics.med-ph) ,business ,Algorithm ,Blood Flow Velocity - Abstract
Three-dimensional cardiovascular fluid dynamics simulations typically require computation of several cardiac cycles before they reach a periodic solution, rendering them computationally expensive. Furthermore, there is currently no standardized method to determine whether a simulation has yet reached that periodic state. In this work, we propose the use of an asymptotic error measurement to quantify the difference between simulation results and their ideal periodic state using open-loop lumped-parameter modeling. We further show that initial conditions are crucial in reducing computational time and develop an automated framework to generate appropriate initial conditions from a one-dimensional model of blood flow. We demonstrate the performance of our initialization method using six patient-specific models from the Vascular Model Repository. In our examples, our initialization protocol achieves periodic convergence within one or two cardiac cycles, leading to a significant reduction in computational cost compared to standard methods. All computational tools used in this work are implemented in the open-source software platform SimVascular. Automatically generated initial conditions have the potential to significantly reduce computation time in cardiovascular fluid dynamics simulations.
- Published
- 2021
34. Allosteric modulation of β-cell M 3 muscarinic acetylcholine receptors greatly improves glucose homeostasis in lean and obese mice
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James E. Melvin, Diptadip Dattaroy, Jürgen Wess, Mario Rossi, Jennifer Langel, Nicolai M. Doliba, Hongchao Zheng, Taro Mukaibo, Franz M. Matschinsky, Lu Zhu, Daniel H. Appella, Samer Hattar, Jonathan Pham, and Amanda Cohen
- Subjects
0301 basic medicine ,medicine.medical_specialty ,Multidisciplinary ,Allosteric modulator ,Chemistry ,Insulin ,medicine.medical_treatment ,Pancreatic islets ,Allosteric regulation ,030209 endocrinology & metabolism ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Endocrinology ,medicine.anatomical_structure ,Internal medicine ,Muscarinic acetylcholine receptor ,medicine ,Glucose homeostasis ,Receptor ,Acetylcholine ,medicine.drug - Abstract
Given the global epidemic in type 2 diabetes, novel antidiabetic drugs with increased efficacy and reduced side effects are urgently needed. Previous work has shown that M3 muscarinic acetylcholine (ACh) receptors (M3Rs) expressed by pancreatic β cells play key roles in stimulating insulin secretion and maintaining physiological blood glucose levels. In the present study, we tested the hypothesis that a positive allosteric modulator (PAM) of M3R function can improve glucose homeostasis in mice by promoting insulin release. One major advantage of this approach is that allosteric agents respect the ACh-dependent spatiotemporal control of M3R activity. In this study, we first demonstrated that VU0119498, a drug known to act as a PAM at M3Rs, significantly augmented ACh-induced insulin release from cultured β cells and mouse and human pancreatic islets. This stimulatory effect was absent in islets prepared from mice lacking M3Rs, indicative of the involvement of M3Rs. VU0119498 treatment of wild-type mice caused a significant increase in plasma insulin levels, accompanied by a striking improvement in glucose tolerance. These effects were mediated by β-cell M3Rs, since they were absent in mutant mice selectively lacking M3Rs in β cells. Moreover, acute VU0119498 treatment of obese, glucose-intolerant mice triggered enhanced insulin release and restored normal glucose tolerance. Interestingly, doses of VU0119498 that led to pronounced improvements in glucose homeostasis did not cause any significant side effects due to activation of M3Rs expressed by other peripheral cell types. Taken together, the data from this proof-of-concept study strongly suggest that M3R PAMs may become clinically useful as novel antidiabetic agents.
- Published
- 2019
35. Shabat polynomials and monodromy groups of trees uniquely determined by ramification type
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Naiomi T. Cameron, Austin Wei, Mary Kemp, Gabrielle Melamed, Richard A. Moy, Jonathan Pham, and Susan Maslak
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Pure mathematics ,dessins d'enfant ,11G32 ,General Mathematics ,Ramification (botany) ,010102 general mathematics ,14H57 ,trees ,15. Life on land ,Type (model theory) ,01 natural sciences ,monodromy groups ,Nonlinear Sciences::Exactly Solvable and Integrable Systems ,Mathematics::Algebraic Geometry ,Monodromy ,Shabat polynomials ,wreath products ,0103 physical sciences ,Belyi maps ,010307 mathematical physics ,20E22 ,0101 mathematics ,Mathematics - Abstract
A dessin d’enfant or dessin is a bicolored graph embedded into a Riemann surface. Acyclic dessins can be described analytically by preimages of Shabat polynomials and algebraically by their monodromy groups. We determine the Shabat polynomials and monodromy groups of planar acyclic dessins that are uniquely determined by their ramification types.
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- 2019
36. The Association Between Genetic Ancestry and Asthma Risk, Across Different Ethnicities and Host Countries: A Systematic Review
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Dinh S Bui, Aung Ko Win, Jonathan Pham, Shyamali C. Dharmage, Mark Hew, C. Lodge, and Michael J. Abramson
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Host (biology) ,business.industry ,Genetic genealogy ,Association (object-oriented programming) ,medicine ,Ethnic group ,medicine.disease ,business ,Asthma ,Demography - Published
- 2021
37. The Cost of Guideline Adherence: A Multicenter Analysis of the Financial Implications of Adopting the US Multi-Society Task Force Polypectomy Guidelines
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Ryan Kahl, Emily Lin, Andrew P. Wright, Harika Balagoni, Nathan Oh, Jonathan Pham, Kelli Kam, Mohamed Azab, and Marc S. Piper
- Subjects
Finance ,Academic Medical Centers ,medicine.diagnostic_test ,Guideline adherence ,business.industry ,Task force ,medicine.medical_treatment ,Forceps ,Gastroenterology ,Colonoscopy ,Colonic Polyps ,Community Health Centers ,Surgical Instruments ,Polypectomy ,medicine ,Community practice ,Humans ,Guideline Adherence ,Disposable Equipment ,business ,Colorectal Neoplasms ,Reimbursement - Abstract
GOAL The goal of this study was to determine the financial impact of adopting the US Multi-Society Task Force (USMSTF) polypectomy guidelines on physician reimbursement and disposable equipment costs for gastroenterologists in the academic medical center and community practice settings. BACKGROUND In 2020, USMSTF guidelines on polypectomy were introduced with a strong recommendation for cold snare rather than cold forceps technique for removing diminutive and small polyps. Polypectomy with snare technique reimburses physicians at a higher rate compared with cold forceps and also requires different disposable equipment. The financial implications of adopting these guidelines is unknown. MATERIALS AND METHODS Patients that underwent screening colonoscopy where polypectomy was performed at an academic medical center (Loma Linda University Medical Center) and community practice medical center (Ascension Providence Hospital) between July 2018 and July 2019 were identified. The polypectomy technique performed during each procedure was determined (forceps alone, snare alone, forceps plus snare) along with the number and size of polyps as well as disposable equipment. Actual and projected provider reimbursement and disposable equipment costs were determined based on applying the new polypectomy guidelines. RESULTS A total of 1167 patients underwent colonoscopy with polypectomy. Adhering to new guidelines would increase estimated physician reimbursement by 5.6% and 12.5% at academic and community practice sites, respectively. The mean increase in physician reimbursement per procedure was significantly higher at community practice compared with the academic setting ($29.50 vs. $14.13, P
- Published
- 2021
38. Sleep assessment by means of a wrist actigraphy-based algorithm: agreement with polysomnography in an ambulatory study on older adults
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Jonathan Pham, Rani A. Sarkis, Francesco Onorati, Matteo Lai, Giulia Gerboni, Rosalind W. Picard, Matteo Migliorini, Nirajan Puri, Giulia Regalia, and Milena Pavlova
- Subjects
Physiology ,Polysomnography ,030209 endocrinology & metabolism ,Wrist ,03 medical and health sciences ,0302 clinical medicine ,Physiology (medical) ,medicine ,Humans ,Aged ,Sleep quality ,medicine.diagnostic_test ,business.industry ,Sleep assessment ,Reproducibility of Results ,Actigraphy ,Circadian Rhythm ,medicine.anatomical_structure ,Diverse population ,Ambulatory ,business ,Sleep ,human activities ,Algorithm ,030217 neurology & neurosurgery ,Algorithms - Abstract
The purpose of the present work is to examine, on a clinically diverse population of older adults (N = 46) sleeping at home, the performance of two actigraphy-based sleep tracking algorithms (i.e., Actigraphy-based Sleep algorithm, ACT-S1 and Sadeh's algorithm) compared to manually scored electroencephalography-based PSG (PSG-EEG). ACT-S1 allows for a fully automatic identification of sleep period time (SPT) and within the identified sleep period, the sleep-wake classification. SPT detected by ACT-S1 did not differ statistically from using PSG-EEG (bias = -9.98 min; correlation 0.89). In sleep-wake classification on 30-s epochs within the identified sleep period, the new ACT-S1 presented similar or slightly higher accuracy (83-87%), precision (86-89%) and F1 score (90-92%), significantly higher specificity (39-40%), and significantly lower, but still high, sensitivity (96-97%) compared to Sadeh's algorithm, which achieved 99% sensitivity as the only measure better than ACT-S1's. Total sleep times (TST) estimated with ACT-S1 and Sadeh's algorithm were higher, but still highly correlated to PSG-EEG's TST. Sleep quality metrics of sleep period efficiency and wake-after-sleep-onset computed by ACT-S1 were not significantly different from PSG-EEG, while the same sleep quality metrics derived by Sadeh's algorithm differed significantly from PSG-EEG. Agreement between ACT-S1 and PSG-EEG reached was highest when analyzing the subset of subjects with least disrupted sleep (N = 28). These results provide evidence of promising performance of a full-automation of the sleep tracking procedure with ACT-S1 on older adults. Future longitudinal validations across specific medical conditions are needed. The algorithm's performance may further improve with integrating multi-sensor information.
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- 2020
39. Creation and evolution of roughness on silica under unlubricated wear
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Son-Jonathan Pham-Ba and Jean-François Molinari
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wear ,Materials science ,third-body layer ,friction ,FOS: Physical sciences ,02 engineering and technology ,Surface finish ,Condensed Matter - Soft Condensed Matter ,Critical length ,Molecular dynamics ,Brittleness ,0203 mechanical engineering ,Materials Chemistry ,Surface roughness ,Composite material ,Range (particle radiation) ,Steady state ,Time evolution ,Surfaces and Interfaces ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,molecular dynamics ,Surfaces, Coatings and Films ,pin-on-disc ,020303 mechanical engineering & transports ,silica ,Mechanics of Materials ,surface roughness ,Soft Condensed Matter (cond-mat.soft) ,0210 nano-technology - Abstract
Friction and wear are important phenomena occurring in all devices with moving parts. While their origin and the way they evolve over time are not fully understood, they are both intimately linked to surface roughness. Guided by pin-on-disc experiments, we present the steps giving rise to the formation of surface roughness on silica, first by the creation of roughly spherical wear particles whose size is related to a critical length scale governing the transition between ductile and brittle behavior, then by the accumulation of these small particles into a larger third body layer, or gouge. We show that, for the explored range of loading conditions, the surface roughness evolves toward a common steady state under unlubricated wear regardless of the initial surface roughness, hinting toward the possible predictability of roughness evolution in wearing components. The friction coefficient is shown to be related to the surface roughness and its time evolution is discussed as well., 12 pages, 10 figures, published in Wear
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- 2020
40. Serum thrombospondin 2 is a novel predictor for the severity in the patients with NAFLD
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Jonathan Pham, Yuichi Iwashita, Naoki Tanaka, Takeji Umemura, Sai Prasad Pydi, Satoru Joshita, Naoyuki Fujimori, Takahito Katsuyama, Tomoo Yamazaki, and Takefumi Kimura
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Liver Cirrhosis ,medicine.medical_specialty ,Hepatology ,medicine.diagnostic_test ,business.industry ,Biopsy ,Fatty liver ,medicine.disease ,Gastroenterology ,Cytokeratin ,Ballooning degeneration ,Type IV collagen ,Liver ,Fibrosis ,Non-alcoholic Fatty Liver Disease ,Internal medicine ,Liver biopsy ,medicine ,Humans ,business ,Thrombospondins ,Biomarkers ,Retrospective Studies - Abstract
AIM Thrombospondins are a family of multidomain and secretory glycoproteins. Among them, thrombospondin 2 (TSP2) encoded by TSP2 gene has been reported to be involved in various functions such as collagen/fibrin formation, maintenance of normal blood vessel density and cell adhesion properties. Microarray analyses ranked TSP2 as one of the most highly up-regulated genes in the fibrotic liver in patients with non-alcoholic fatty liver disease (NAFLD). Since TSP2 possesses unique properties as a secretory protein, we hypothesized that hepatic TSP2 gene expression levels would be reflected in serum TSP2 levels. In this study, we examined the relationship between serum TSP2 concentrations and clinicopathological findings in NAFLD patients. METHODS One hundred and thirty NAFLD patients who had undergone liver biopsy between 2009 and 2015 were retrospectively enrolled. Serum samples were collected at the time of biopsy, and TSP2 was measured by enzyme immunoassays. RESULTS Serum TSP2 levels moderately correlated with ballooning (r = 0.56, P
- Published
- 2020
41. Predictors of bleeding in patients receiving direct oral anticoagulants
- Author
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Mahesan Anpalahan, Geoh Soon Chua, and Jonathan Pham
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medicine.medical_specialty ,Renal function ,Administration, Oral ,Hemorrhage ,030204 cardiovascular system & hematology ,Logistic regression ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,Atrial Fibrillation ,Internal Medicine ,medicine ,Humans ,In patient ,030212 general & internal medicine ,Aged ,Retrospective Studies ,Medical unit ,Potential risk ,business.industry ,Incidence (epidemiology) ,Medical record ,Anticoagulants ,business ,Major bleeding ,Platelet Aggregation Inhibitors - Abstract
Background The predictors of clinically significant bleeding events (CSBEs) associated with direct oral anticoagulants (DOACs) are poorly characterised in literature. Aim To determine the incidence and predictors of CSBEs in patients receiving DOACs. Methods Patients who received DOACs during admission under a general medical unit over a two-year period were retrospectively studied. Following index admission, patients were followed for 12 months or for the duration of treatment (if the latter was less than 12 months). The relevant data were obtained by review of medical records. Results A total of 203 patients were studied over a mean follow-up period of 293 (±81) days. The incidence of CSBE was 13.7 (95%CI 9.5-21.1) per 100 person-years. Age ≥ 75 years (P=0.01), concurrent use of antiplatelet medications (P=0.02) and lower estimated creatinine clearance (CrCl) (P=0.03) had a significant univariate association with CSBEs. However, in the multivariate logistic regression only concurrent use of antiplatelet medications remained significantly associated with CSBEs (adjusted OR3.6, 95%CI:1.4-9.6, P=0.01). Concurrent use of antiplatelet medications was also independently associated with major bleeding events (MBEs) (adjusted OR4.9, 95%CI:1.1-21.4, P=0.04). Although 39 (19.2%) patients received antiplatelet medications, the indications for concurrent antiplatelet use complied with current guidelines in only 3 (7.7%) patients. Conclusion Caution should be exercised when prescribing antiplatelet medications with DOACs, as this combination is a potential risk factor for both major and non-major clinically significant bleeding events. In most patients, the concurrent use of antiplatelet medications was discordant with the current consensus guidelines. This article is protected by copyright. All rights reserved.
- Published
- 2020
42. Updated prevalence, predictors and treatment outcomes for bronchiolitis obliterans syndrome after allogeneic stem cell transplantation
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Eli Dabscheck, Tiffany Lin, Maitri Munsif, Catherine Martin, Jonathan Pham, Sharon Avery, Jhanavi Rangaswamy, and Brigitte M. Borg
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Pulmonary and Respiratory Medicine ,Spirometry ,medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,medicine.medical_treatment ,Bronchiolitis obliterans ,Context (language use) ,Immunosuppression ,Disease ,medicine.disease ,humanities ,Transplantation ,03 medical and health sciences ,0302 clinical medicine ,Clinical research ,030228 respiratory system ,Internal medicine ,medicine ,030212 general & internal medicine ,business ,Progressive disease - Abstract
Introduction Bronchiolitis obliterans syndrome (BOS) after allogeneic haemopoietic stem cell transplant (HSCT) is an under-recognised and difficult to treat disease. This occurs in the context of limited clinical research and inconsistent diagnostic criteria. Method Retrospective data was collected on 275 patients who underwent allogeneic HSCT at an Australian tertiary hospital between 2007 and 2017. The prevalence of BOS, defined by 2014 National Institute of Health criteria, as well as predictors for BOS and mortality were determined. Treatment outcomes, using serial spirometry, were compared between patients who received early versus late immunosuppression for BOS. Results The prevalence of BOS was 9.1%. Myeloablative conditioning (OR: 2.7, 95%CI: 1.13–6.50, p = 0.03) and extra-pulmonary chronic graft-versus-host disease (OR 2.62, 95% CI: 1.04–6.60, p = 0.04) were associated with BOS. There was reduced median survival in the BOS group compared with the non-BOS group, but this was not statistically significant (4.1years (IQR: 2.8, 6.8) versus 4.6years (IQR: 2.4, 7.8), respectively, p = 0.33). The vast majority (87.5%) of BOS patients failed to attain improvement in FEV1 at 12 months, regardless of treatment strategy. Patients who underwent a late immunosuppression strategy had worse mean FEV1 decline compared to those who received early immunosuppression (−36.3% versus −1.6%, respectively, p = 0.03). Conclusion BOS is a common and progressive disease following HSCT and is largely refractory to current treatment strategies. Compared to late immunosuppression, early augmentation of immunosuppression may slow lung function deterioration in the short term. However, further research is urgently needed to identify effective prevention and treatment strategies for BOS.
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- 2020
43. Comparison and evaluation of distortion correction techniques on an MR-guided radiotherapy system
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Ricky R. Savjani, Jonathan Pham, Ann C. Raldow, Stephanie M. Yoon, Yingli Yang, Yu Gao, Peng Hu, Daniel A. Low, and Anusha Kalbasi
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Physics ,Distortion correction ,Echo-Planar Imaging ,Phantoms, Imaging ,Bandwidth (signal processing) ,Reproducibility of Results ,General Medicine ,Repeatability ,Imaging phantom ,030218 nuclear medicine & medical imaging ,03 medical and health sciences ,0302 clinical medicine ,Diffusion Magnetic Resonance Imaging ,Sørensen–Dice coefficient ,030220 oncology & carcinogenesis ,Effective diffusion coefficient ,Humans ,Artifacts ,Algorithm ,Mri guided ,Diffusion MRI ,Radiotherapy, Image-Guided - Abstract
PURPOSE To evaluate two distortion correction techniques for diffusion-weighted single-shot echo-planar imaging (DW-ssEPI) on a 0.35 T magnetic resonance-guided radiotherapy (MRgRT) system. METHODS The effects of sequence optimization through enabling parallel imaging (PI) and selecting appropriate bandwidth on spatial distortion were first evaluated on the 0.35 T MRgRT system using a spatial integrity phantom. Field map (FM) and reversed gradient (RG) corrections were then performed on the optimized protocol to further reduce distortion. An open-source toolbox was used to quantify the spatial displacement before and after distortion correction. To evaluate ADC accuracy and repeatability of the optimized protocol, as well as impacts of distortion correction on ADC values, the optimized protocol was scanned twice on a diffusion phantom. The calculated ADC values were compared with reference ADCs using paired t-test. Intraclass correlation coefficient (ICC) between the two repetitions, as well as between before and after FM/RG correction was calculated to evaluate ADC repeatability and effects of distortion correction. Six patients were recruited to assess the in-vivo performance. The optimal distortion correction technique was identified by visual assessment. To quantify distortion reduction, tumor and critical structures were contoured on the turbo spin echo (TSE) image (reference image), the DW-ssEPI image, and the distortion corrected images independently by two radiation oncologists. Mean distance to agreement (MDA) and DICE coefficient between contours on the reference images and the diffusion images were calculated. Tumor apparent diffusion coefficient (ADC) values from the original DW-ssEPI images and the distortion corrected images were compared using Bland-Altman analysis. RESULTS Sequence optimization played a vital role in improving the spatial integrity, and spatial distortion was proportional to the total readout time. Before the correction, distortion of the optimized protocol (PI and high bandwidth) was 1.50 ± 0.89 mm in a 100 mm radius and 2.21 ± 1.39 mm in a 175 mm radius for the central plane. FM corrections reduced the distortions to 0.42 ± 0.27 mm and 0.67 ± 0.49 mm respectively, and RG reduced distortion to 0.40 ± 0.22 mm and 0.64 ± 0.47 mm, respectively. The optimized protocol provided accurate and repeatable ADC quantification on the diffusion phantom. The calculated ADC values were consistent before and after FM/RG correction. For the patient study, the FM correction was unable to reduce chemical shift artifacts whereas the RG method successfully mitigated the chemical shift. MDA reduced from 2.52 ± 1.29 mm to 1.11 ± 0.72 mm after the RG correction. The DICE coefficient increased from 0.80 ± 0.13 to 0.91 ± 0.06. A Bland-Altman plot showed that there was a good agreement between ADC measurements before and after application of the RG correction. CONCLUSION Two distortion correction techniques were evaluated on a commercial low-field MRgRT system. Overall, the RG correction was able to drastically improve spatial distortion and preserve ADC accuracy.
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- 2020
44. Objectively measured sleep-wake patterns in patients with drug-resistant epilepsy - Interaction with quality of life and antiepileptic treatment
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Véronique Latreille, Wei Wang, Jonathan Pham, Milena Pavlova, and Judith Ramel
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Adult ,Sleep Wake Disorders ,Pediatrics ,medicine.medical_specialty ,Clobazam ,Bedtime ,03 medical and health sciences ,Behavioral Neuroscience ,Epilepsy ,0302 clinical medicine ,medicine ,Humans ,030212 general & internal medicine ,Prospective Studies ,business.industry ,Epworth Sleepiness Scale ,Sleep apnea ,Actigraphy ,Drug Resistant Epilepsy ,medicine.disease ,Neurology ,Pharmaceutical Preparations ,Quality of Life ,Anticonvulsants ,Neurology (clinical) ,Sleep onset ,business ,Sleep ,030217 neurology & neurosurgery ,medicine.drug - Abstract
Rationale Patients with epilepsy experience frequent episodes of fragmented sleep which may contribute to chronic sleep loss. Enhancing sleep patterns might lead to improved quality of life in these patients. Currently, unlike some other antiepileptic drugs (AEDs), there are no data on the effects of clobazam, a novel AED on sleep. Therefore, we tested the hypothesis that patients with epilepsy will have longer, more consolidated sleep after treatment with clobazam. Methods In this prospective study, we included adults with drug-resistant epilepsy who were being considered for treatment with clobazam. Patients with known untreated moderate/severe sleep apnea or with major circadian rhythm disorders were excluded. We tested a set of the following subjective sleep measures: Pittsburgh Sleep Quality Inventory (PSQI), Epworth Sleepiness Scale (ESS), Karolinska Sleepiness Scale (KSS), Insomnia Severity Index (ISI), and Quality of Life in Epilepsy (QOLIE) prior to starting the treatment, as well as after achieving a stable clobazam dose. We also measured sleep pattern using wrist actigraphy – before starting therapy and after achieving stable dose. Results A total of 12 participants completed all parts of the study. After treatment, a lower number of awakenings and less wake after sleep onset (WASO) were seen, as well as a lower number of seizures. Average pretreatment bedtime was 23:45, and average wake time was 8:24. A higher seizure frequency significantly correlated with all subjective sleep measures, as well as with a higher amount actigraphy measured WASO and less total sleep time (TST) measured both by sleep log and by actigraphy. Those with higher baseline WASO by actigraphy also had more depressive symptoms, worse quality of life, longer duration of epilepsy, and a higher seizure frequency. Conclusion Both objective and subjective sleep metrics correlate with depressive symptoms and quality of life. After treatment, there were fewer awakenings as well as fewer seizures.
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- 2020
45. Invasive liver abscess syndrome accompanied by spondylodiscitis: a case report and review of the literature
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Jun'ichi Kobayashi, Jonathan Pham, Shun-Ichi Wakabayashi, Tomoyuki Tanaka, Takeji Umemura, Naoki Tanaka, Akihiro Iijima, Shohei Higuchi, and Takefumi Kimura
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Spondylodiscitis ,Male ,medicine.medical_specialty ,Discitis ,Liver Abscess ,Lumbar vertebrae ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Humans ,Abscess ,Spondylitis ,Aged ,business.industry ,Gastroenterology ,General Medicine ,Hepatology ,medicine.disease ,Thrombosis ,Surgery ,Anti-Bacterial Agents ,Klebsiella pneumoniae ,medicine.anatomical_structure ,030220 oncology & carcinogenesis ,030211 gastroenterology & hepatology ,Iliopsoas ,business ,Tomography, X-Ray Computed ,Liver abscess - Abstract
A 65-year-old man who had diabetes mellitus was referred to our hospital due to fever and back pain. Laboratory findings showed liver dysfunction and C-reactive protein (CRP) elevation. Enhanced computed tomography (CT) showed multiple liver abscesses, hepatic vein and inferior vena cava thrombosis, and spondylodiscitis in the fourth lumbar vertebrae. Based on several detections of Klebsiella pneumoniae (K. pneumoniae) in blood culture, he was diagnosed as having invasive liver abscess syndrome (ILAS), which is characterized by liver abscess and metastatic infection caused by K. pneumoniae. Despite the prompt improvement of liver abscess and thrombosis, after administering antibiotics and anticoagulant, spondylodiscitis worsened. Additionally, iliopsoas abscess emerged on repeated CT imaging. Lumbar laminectomy was needed as a radical treatment. We reviewed 12 cases of ILAS representing spondylodiscitis, and surgical treatments for spondylodiscitis were required in 7 of these cases (58%). When encountering patients with liver abscess and spondylodiscitis, we should consider the possibility of invasive disseminated K. pneumoniae infection, which is hard to treat with antibiotics alone and sometimes requires surgical treatments for spondylodiscitis.
- Published
- 2020
46. Addressing the impact of ethnicity on asthma care
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Jonathan Pham, Tunn Ren Tay, and Mark Hew
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Gerontology ,Immunology ,MEDLINE ,Ethnic group ,Asthma care ,Health Services Accessibility ,Health care ,medicine ,Ethnicity ,Immunology and Allergy ,Humans ,Healthcare Disparities ,Precision Medicine ,Minority Groups ,Asthma ,business.industry ,Self-Management ,Emigration and Immigration ,medicine.disease ,respiratory tract diseases ,Disadvantaged ,Socioeconomic Factors ,Well-being ,Patient Compliance ,business ,Psychosocial - Abstract
Purpose of review In asthma, there is an increasing focus on personalizing treatment by targeting treatable traits. Ethnicity has effects on many biological and behavioural traits, and so is an important consideration when personalizing asthma care. This review has particular relevance in light of current patterns of international migration, which are leading to unprecedented levels of ethnic heterogeneity in many geographic regions. Recent findings This review examines the effect of ethnicity on three key domains - biological traits, behavioural traits and health system behaviour. Ethnicity influences asthma biology by affecting biomarker reference ranges, response to drug therapy and asthma phenotypes. Ethnicity impacts behavioural traits through its effects on psychosocial well being, adherence and asthma self-management. Ethnic minorities are often disadvantaged with regards to healthcare access and healthcare interactions. Summary Concerted action is needed to address current issues around behavioural traits and healthcare behaviour, which are influenced by ethnicity. More research is required to understand the impact of ethnicity on asthma biology, especially the interplay between genetic and environmental influences on asthma, and the differential response to asthma therapies.
- Published
- 2019
47. Polysomnographic comparison between Chinese and Caucasian patients with obstructive sleep apnea
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Jonathan Pham, Denise M. O'Driscoll, Alan Young, and Y. T. Kuo
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medicine.medical_specialty ,Lung ,Neurology ,Physiology ,business.industry ,Apnea ,medicine.disease ,respiratory tract diseases ,Hypoxemia ,Obstructive sleep apnea ,03 medical and health sciences ,0302 clinical medicine ,Neuropsychology and Physiological Psychology ,medicine.anatomical_structure ,030228 respiratory system ,Control of respiration ,Physiology (medical) ,Internal medicine ,medicine ,Mass index ,medicine.symptom ,business ,Hypopnea ,030217 neurology & neurosurgery - Abstract
The Chinese population has a comparable prevalence of obstructive sleep apnea (OSA) compared to their Caucasian counterparts, but are notably less obese. Given this difference in body weight, Chinese patients could have a distinct OSA phenotype. We aimed to compare the characteristics of obstructive events in Chinese and Caucasian individuals matched for OSA severity. Chinese and Caucasian subjects with moderate-to-severe OSA (apnea–hypopnea index (AHI) ≥ 20events/h) were included in the study (n = 90) and matched for age, gender and AHI. Data were analysed to identify differences in event type, effect of sleep state and body position, degree of hypoxemia, and prevalence of metabolic risk factors. Data presented are Mean ± SEM or Median (IQR). Chinese subjects had a significantly lower body mass index (BMI) compared to AHI-matched Caucasian counterparts [27 (25–30) versus 34 (30–39) kg/m2, p
- Published
- 2018
48. MA04.09 Impacts of Multidisciplinary Meeting Presentation: Drivers and Outcomes from a Population Registry Retrospective Cohort study
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Susan Harden, John Zalcberg, T. Lin, Robert G Stirling, Philip B. Mitchell, Jonathan Pham, Matthew Conron, N. Atkin, Gavin M. Wright, E. Paul, David Ball, and Margaret Brand
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,education.field_of_study ,Oncology ,business.industry ,Multidisciplinary approach ,Family medicine ,Population ,medicine ,Retrospective cohort study ,Presentation (obstetrics) ,education ,business - Published
- 2021
49. Androgenic to oestrogenic switch in the human adult prostate gland is regulated by epigenetic silencing of steroid 5α-reductase 2
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Zongwei Wang, Chin-Lee Wu, Shulin Wu, Douglas W. Strand, Seth Bechis, Rongbin Ge, Libing Hu, Shahin Tabatabaei, Keyan Salari, Aria F. Olumi, Jonathan Pham, and Cyrus Rassoulian
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0301 basic medicine ,medicine.medical_specialty ,biology ,Prostatic Stroma ,Prostatic Diseases ,Hyperplasia ,medicine.disease ,Pathology and Forensic Medicine ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Endocrinology ,medicine.anatomical_structure ,Prostate ,030220 oncology & carcinogenesis ,SRD5A2 ,Internal medicine ,biology.protein ,medicine ,Epigenetics ,Aromatase ,Testosterone - Abstract
Benign prostatic hyperplasia is the most common proliferative abnormality of the prostate. All men experience some prostatic growth as they age, but the rate of growth varies among individuals. Steroid 5α-reductase 2 (SRD5A2) is a critical enzyme for prostatic development and growth. Previous work indicates that one-third of adult prostatic samples do not express SRD5A2, secondary to epigenetic modifications. Here we show that the level of oestradiol is dramatically elevated, concomitant with significant upregulation of oestrogen response genes, in prostatic samples with methylation at the SRD5A2 promoter. The phosphorylation of oestrogen receptor-α in prostatic stroma is upregulated when SRD5A2 expression is absent. We show that tumour necrosis factor (TNF)-α suppresses SRD5A2 mRNA and protein expression, and simultaneously promotes expression of aromatase, the enzyme responsible for conversion of testosterone to oestradiol. Concomitant suppression of SRD5A2 and treatment with TNF-α synergistically upregulate the aromatase levels. The data suggest that, in the absence of prostatic SRD5A2, there is an androgenic to oestrogenic switch. These findings have broad implications for choosing appropriate classes of medications for the management of benign and malignant prostatic diseases. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
- Published
- 2017
50. Conducting hydrogels for edible electrodes
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Jonathan Pham, Holly Warren, Marc in het Panhuis, and Alexander Keller
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food.ingredient ,Materials science ,Biomedical Engineering ,Food grade ,Nanotechnology ,02 engineering and technology ,General Chemistry ,General Medicine ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Capacitive pressure sensor ,01 natural sciences ,Gelatin ,Gellan gum ,0104 chemical sciences ,Intestinal motility ,chemistry.chemical_compound ,food ,Chemical engineering ,chemistry ,Electrode ,Self-healing hydrogels ,General Materials Science ,0210 nano-technology - Abstract
The development of highly swollen, strong, conductive hydrogel materials is necessary for the advancement of edible device research. Using a gellan gum/gelatin ionic-covalent entanglement (ICE) hydrogel, a simple method of producing conductive, edible hydrogels is described. ICE gels containing NaCl or CsCl were developed which exhibited conductivities of 200 ± 20 mS cm−1 and 380 ± 30 mS cm−1, respectively. Furthermore, the potential of food grade products for use as edible electrodes was examined by analysing the electrical properties of alginate–gelatin hydrogels, Vegemite, Marmite, jelly and gold leaf. Lastly, these edible ICE gels were used to demonstrate a capacitive pressure sensor from consumable materials, which displayed a sensitivity of 0.80 ± 0.06 pF kPa−1 for a range of 4–20 kPa. The pressure exerted by the GI tract on its contents is standardly 0.7 kPa to 6.3 kPa. This suggests potential for application in the detection of digestive pressure abnormalities such as intestinal motility disorders.
- Published
- 2017
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