37 results on '"Choudhury TA"'
Search Results
2. FruitVision: A deep learning based automatic fruit grading system
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Hayat Ahatsham, Morgado-Dias Fernando, Choudhury Tanupriya, Singh Thipendra P., and Kotecha Ketan
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machine learning ,computer vision ,deep learning ,fruit grading ,agriculture ,Agriculture ,Agriculture (General) ,S1-972 - Abstract
Quality assessment of fruits plays a key part in the global economy’s agricultural sector. In recent years, it has been shown that fruits are affected by different diseases, which can lead to widespread economic failure in the agricultural industry. Traditional manual visual grading of fruits could be more accurate, making it difficult for agribusinesses to assess quality efficiently. Automatic grading of fruits using computer vision has become a prominent area of study for many researchers. In this study, a deep learning-based model called FruitVision is proposed for the automatic grading of various fruits. The results showed that FruitVision performed all the existing models and obtained an accuracy of 99.42, 99.50, 99.24, 99.12, 99.38, 99.38, 99.17, 98.86, and 97.96% for the apple, banana, guava, lime, orange, pomegranate, Ajwa date, Mabroom date, and mango, respectively, using 5-fold cross-validation. This is a remarkable achievement in the field of AI-based fruit grading systems.
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- 2024
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3. Artificial intelligence and internet of things oriented sustainable precision farming: Towards modern agriculture
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Sharma Amit, Sharma Ashutosh, Tselykh Alexey, Bozhenyuk Alexander, Choudhury Tanupriya, Alomar Madani Abdu, and Sánchez-Chero Manuel
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iot ,artificial intelligence ,methanol ,renewal energy ,sustainable development ,Biology (General) ,QH301-705.5 - Abstract
Agriculture encompasses the study, practice, and discipline of plant cultivation. Agriculture has an extensive history dating back thousands of years. Depending on climate and terrain, it began independently in various locations on the planet. In comparison to what could be sustained by foraging and gathering, agriculture has the potential to significantly increase the human population. Throughout the twenty-first century, precision farming (PF) has increased the agricultural output. precision agriculture (PA) is a technology-enabled method of agriculture that assesses, monitors, and evaluates the needs of specific fields and commodities. The primary objective of this farming method, as opposed to conventional farming, is to increase crop yields and profitability through the precise application of inputs. This work describes in depth the development and function of artificial intelligence (AI) and the internet of things (IoT) in contemporary agriculture. Modern day-to-day applications rely extensively on AI and the IoT. Modern agriculture leverages AI and IoT for technological advancement. This improves the accuracy and profitability of modern agriculture. The use of AI and IoT in modern smart precision agricultural applications is highlighted in this work and the method proposed incorporates specific steps in PF and demonstrates superior performance compared to existing classification methods. It achieves a remarkable accuracy of 98.65%, precision of 98.32%, and recall rate of 97.65% while retaining competitive execution time of 0.23 s, when analysing PF using the FAOSTAT benchmark dataset. Additionally, crucial equipment and methods used in PF are described and the vital advantages and real-time tools utilised in PA are covered in detail.
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- 2023
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4. A novel hybrid ensemble convolutional neural network for face recognition by optimizing hyperparameters
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Anwarul Shahina, Choudhury Tanupriya, and Dahiya Susheela
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ensemble learning ,face detection ,face recognition ,hyperparameters tuning ,transfer learning ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
A fully fledged face recognition system consists of face detection, face alignment, and face recognition. Facial recognition has been challenging due to various unconstrained factors such as pose variation, illumination, aging, partial occlusion, low resolution, etc. The traditional approaches to face recognition have some limitations in an unconstrained environment. Therefore, the task of face recognition is improved using various deep learning architectures. Though the contemporary deep learning techniques for face recognition systems improved overall efficiency, a resilient and efficacious system is still required. Therefore, we proposed a hybrid ensemble convolutional neural network (HE-CNN) framework using ensemble transfer learning from the modified pre-trained models for face recognition. The concept of progressive training is used for training the model that significantly enhanced the recognition accuracy. The proposed modifications in the classification layers and training process generated best-in-class results and improved the recognition accuracy. Further, the suggested model is evaluated using a self-created criminal dataset to demonstrate the use of facial recognition in real-time. The suggested HE-CNN model obtained an accuracy of 99.35, 91.58, and 95% on labeled faces in the wild (LFW), cross pose LFW, and self-created datasets, respectively.
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- 2023
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5. A review of tiger conservation studies using nonlinear trajectory: A telemetry data approach
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Choudhary Richa, Dahiya Susheela, and Choudhury Tanupriya
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tiger ,radio telemetry ,telemetry ,radio collars ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
Radio telemetry is being used in India to capture the location and movements of radio-collared wild animals. Radio telemetry data analysis has changed the scenario for wildlife conservation. It has provided many models and solutions for natural habitat utilization, genetic diversity, and even implementing green corridors for the species. Insights drawn from the data collected through radio telemetry from radio-collared animals have provided impactful information to understand the wild animal’s ecology. In the past few years, India has remarkably improved the population of tigers using telemetry studies and other conservation methods. In this study, a review of the telemetry studies conducted for tigers in India in the past decade has been presented. This study summarizes the telemetry studies of tigers in India and discusses how telemetry has enhanced the knowledge of ecologists and scientists to understand tiger ecology. This study also discusses the challenges and issues of conducting telemetry studies on tigers in India. Finally, the authors address the gaps in understanding the tiger’s ecology based on these studies and outline how radio telemetry can address these issues to better understand and conserve tigers.
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- 2023
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6. Study of Gender-based In-Hospital Mortality Difference in Patients with Acute Myocardial Infarction
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Majumder, NK, primary, Khan, MR, primary, Kar, Nupur, primary, Akhtaruzzaman, M, primary, Choudhury, TA, primary, Ali, M Atahar, primary, and Faruque, GM, primary
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- 2018
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7. Path reader and intelligent lane navigator by autonomous vehicle
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Shukla Amar, Verma Ankit, Mahdi Hussain Falih, Choudhury Tanupriya, and Singh Thipendra Pal
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convolution neural network ,pavement condition ,congestion condition ,pothole condition ,traffic light condition ,Technology - Abstract
Internet of Things (IoT) is a physical network of physical devices, such as widgets, structures, and other objects, which can store program, sensors, actuators, and screen configurations to allow the objects to assemble, control, display, and exchange data. The aim of this research was to develop an autonomous system with automated navigation. Using this approach, we are able to make use of deep neural networks for automatic navigation as well as the identification of pot holes and road conditions. Additionally, it displays potholes in traffic and the correct lane on the screen. The system stresses how important it is to select the path from one node to the next.
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- 2023
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8. Drug-Eluting Stent (DES) Induced Coronary Artery Aneurysm - A Rare Case Report
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Choudhury, K, primary, Akhtaruzzaman, M, primary, Khalequzzaman, M, primary, Hasem, S, primary, Choudhury, TA, primary, and Sharafat, NI, primary
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- 2017
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9. Radiofrequency Catheter Ablation of Left-sided Accessory Atrioventricular Pathways at Atrial Insertion Sites
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Hashem, S, primary, Hossain, M, primary, Ali, MA, primary, Chowdhury, AK, primary, Ahsan, Habib SM, primary, Khalequzzaman, M, primary, Akhtaruzzaman, M, primary, Nabi, S, primary, Choudhury, TA, primary, and Sharafat, NI, primary
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- 2014
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10. Drug-Eluting Stent (DES) Induced Coronary Artery Aneurysm - A Case Report
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Choudhury, Amal Kumar, primary, Akhtaruzzaman, M, primary, Khalequzzaman, M, primary, Hasem, S, primary, Choudhury, TA, primary, and Sharafat, NI, primary
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- 2013
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11. Prolonged QTc Dispersion Correlates with Coronary Artery Disease in Acute ST Elevated Myocardial Infarction (STEMI)
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Sharafat, NI, primary, Khalequzzaman, M, primary, Akhtaruzzaman, M, primary, Choudhury, AK, primary, Hasem, S, primary, Choudhury, TA, primary, Nobi, ABM Nurun, primary, MR, Shikder, primary, Kabir, M Shaheen, primary, and Akanda, AK, primary
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- 2013
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12. Hospital-acquired acute kidney injury in medical, surgical, and intensive care unit: A comparative study
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Singh, TB, primary, Rathore, SS, additional, Choudhury, TA, additional, Shukla, VK, additional, Singh, DK, additional, and Prakash, J, additional
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- 2013
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13. Impact of Low Hemoglobin on Contrast-Induced Nephropathy After Percutaneous Coronary Intervention
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Akhtaruzzaman, M, primary, Choudhury, AK, primary, Khalequzzaman, M, primary, Barua, SK, primary, Choudhury, TA, primary, Hasem, S, primary, Majumder, NK, primary, Islam, AKM Monwarul, primary, Chowdhury, S, primary, and Chowdhury, AHK, primary
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- 2012
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14. The impact of a residual atrial communication in patients undergoing complete repair for tetralogy of Fallot: A propensity score-matched analysis.
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Moroi MK, Vinogradsky AV, Nguyen SN, Choudhury TA, Krishnamurthy G, Kalfa D, Bacha EA, Levasseur S, and Goldstone AB
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Background: Surgeons may leave a residual atrial-level communication during complete repair of tetralogy of Fallot (TOF) in anticipation of restrictive right ventricle physiology or as routine practice. We investigated the impact of closing the interatrial communication at the time of definitive TOF repair., Methods: We retrospectively reviewed TOF patients who underwent definitive repair at age <12 months between June 2000 and January 2023. Propensity score matching identified 82 patients with a patent interatrial communication and 50 patients with no interatrial communication on postoperative echocardiography (as-treated analysis). The primary endpoint was maximum vasoactive-inotropic score (VIS) as a surrogate for low cardiac output syndrome., Results: A total of 132 patients (median age, 3.5 months; interquartile range [IQR], 1.8-5.8 months) were matched. There was no difference in maximum VIS (patent interatrial communication: 5.0 [IQR, 4.8-9.0] vs no interatrial communication: 6.0 [IQR, 5.0-8.0]; P = .78). Additionally, the duration of inotrope therapy (3.0 [IQR, 2.0-4.0] days vs 3.0 [IQR, 1.3-4.0] days; P = .57), peak lactate (2.2 [IQR, 1.9-3.0] mmol/L vs 2.3 [IQR, 1.9-3.2] mmol/L; P = .58), time to lactate clearance (0.2 [IQR, 0.0-0.3] days vs 0.1 [IQR, 0.0-0.3] days; P = .57), chest tube duration (4.0 [IQR, 3.0-6.0] days vs 4.0 [IQR, 3.0-5.0] days; P = .23), and length of intensive care unit stay (5.0 [IQR, 3.0-7.0] days vs 5.0 [IQR, 3.0-7.0] days; P = .71) were similar in the 2 groups. The median duration of follow-up was 5.5 years (IQR, 2.7-9.9 years). Among patients with a residual communication, patency rates were 93.6% at discharge and 53.7% at latest follow-up, with most having bidirectional shunting across the defect., Conclusions: Closure of the atrial-level communication during complete TOF repair does not significantly impact the immediate postoperative course or mid-term outcomes. Further investigation is warranted to better understand how patency influences long-term outcomes., Competing Interests: Conflict of Interest Statement The authors reported no conflicts of interest. The Journal policy requires editors and reviewers to disclose conflicts of interest and to decline handling or reviewing manuscripts for which they may have a conflict of interest. The editors and reviewers of this article have no conflicts of interest., (Copyright © 2024 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)
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- 2024
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15. Critical Event Checklists for Simulated In-Hospital Dysrhythmias in Children with Heart Disease.
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Spencer R, Sen AI, Kessler DO, Salabay K, Compagnone T, Zhang Y, and Choudhury TA
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Children with heart disease are at increased risk of unstable dysrhythmias and in-hospital cardiac arrest (IHCA). Clinician adherence to lifesaving processes of care is an important contributor to improving patient outcomes. This study evaluated whether critical event checklists improve adherence to lifesaving processes during simulated acute events secondary to unstable dysrhythmias. A randomized controlled trial was conducted in a cardiac ward in a tertiary care, academic children's hospital. Unannounced simulated emergencies involving dysrhythmias in pediatric patients with underlying cardiac disease were conducted weekly. Responders were pediatric and anesthesiology residents, respiratory therapists, and bedside registered nurses. Six teams were randomized into two groups-three received checklists (intervention) and three did not (control). Each team participated in four simulated scenarios over a 4-week pediatric cardiology rotation. Participants received a brief slideshow presentation, which included a checklist orientation, at the start of their rotation. Simulations were video and audio recorded and those with three or more participants were included for analysis. The primary outcome was team adherence to lifesaving processes, expressed as the percentage of completed critical management steps. Secondary outcomes included participant perceptions of the checklist usefulness in identifying and managing dysrhythmias. We used generalized estimating equations (GEE) models, which accounted for clustering within groups, to evaluate the effects of the intervention. A total of 24 simulations were conducted; one of the 24 simulations was excluded due to an insufficient number of participants. In our GEE analysis, 81.21% (78.96%, 83.47%) of critical steps were completed with checklists available versus 68.06% (59.38%, 76.74%) without checklists (p = 0.004). Ninety-three percent of study participants reported that they would use the checklists during an unstable dysrhythmia of a child with underlying cardiac disease. Checklists were associated with improved adherence to lifesaving processes during simulated resuscitations for unstable pediatric dysrhythmias. These findings support the use of scenario specific checklists for the management of unstable dysrhythmias in simulations involving pediatric patients with underlying cardiac disease. Future studies should investigate whether checklists are as effective in actual pediatric in-hospital emergencies., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2024
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16. Association Between High Sensitivity Troponin Levels Following Pediatric Orthotopic Heart Transplantation and Intensive Care Unit Resource Utilization.
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Butensky AM, Desai S, Dilorenzo M, Lytrivi ID, Mantell BS, Zhang Y, and Choudhury TA
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- Humans, Child, Retrospective Studies, Troponin T, Intensive Care Units, Biomarkers, Troponin, Heart Transplantation
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The utility of troponin levels, including high sensitivity troponin T (hs-TnT), after orthotopic heart transplant (OHT) is controversial. Conflicting data exist regarding its use as a marker of acute rejection. Few studies have examined possible associations of hs-TnT levels immediately after OHT with metrics of intensive care unit (ICU) resource utilization or risk of acute rejection. We performed a retrospective cohort chart review including all OHT recipients < 20 years of age at our center between June 2019 and December 2022. Patients were divided into two groups based on supra- or sub-median initial hs-TnT levels (median 3462.5 ng/L). Primary outcome was days requiring ICU-level care, secondary outcomes included days intubated, days requiring positive pressure ventilation (PPV), days on inotropic medications, actual ICU length of stay, Vasoactive Inotrope Scores (VIS) on postoperative days (POD) 0 through 7, and acute rejection at 30 days and one year after OHT. Patients with higher hs-TnT required ICU level care for longer [13.5 (10-17.5) vs. 9.5 (8-12) days, p = 0.01] and spent more days intubated [6 (4-7) vs. 3 (3-5) days, p < 0.001], on PPV [9 (6-15) vs. 6 (5-8.5) days, p = 0.02], and on inotropes [11 (9-14) vs. 8 (7-11) days, p = 0.025]. VIS was only different between groups on POD7 [5 (3-7) vs. 3 (0-5), p = 0.04]. There was no difference in rejection between the groups. Higher hs-TnT immediately following pediatric OHT may predict higher ICU resource utilization, despite no difference in VIS, although it does not predict acute rejection in the first year after OHT., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
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- 2024
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17. Ventricular Assist Device Training and Emergency Management Among Pediatric Cardiac Intensive Care Physicians - Multicenter Cross-Sectional Survey.
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Esangbedo ID, Yu P, Choudhury TA, Tume SC, and Lasa JJ
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- Child, Humans, United States, Cross-Sectional Studies, Critical Care, Intensive Care Units, Pediatric, Heart-Assist Devices, Physicians
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Background/Aim : Pediatric cardiac intensive care physicians practicing at centers that implant ventricular assist devices (VAD's) are exposed to increasing numbers of VAD patients, with a significant number of VAD-days. We aimed to delineate pediatric cardiac critical care practices surrounding routine and emergency management of VADs. Methodology : We administered a multicenter cross-sectional survey of pediatric cardiac intensive care unit (CICU) physicians in the United States and Canada. Survey distribution occurred between August 31st and October 26th 2021. Results : A total of 254 CICU physicians received a formal invitation to participate, with 108 returning completed surveys (42.5% response rate). Responses came from CICU attending physicians at 26 separate institutions. Respondents' level of experience was well distributed across junior, mid-level, and senior staff: less than 5 years (38%), 5-9 years (25%), and >/= 10 years (37%). Most respondents had received formal training in the management of VAD patients (n = 93, 86.1%), with training format including fellowship (61%), simulation (36%), and national/international conferences (26.5%). Dedicated advanced cardiac therapies teams were available at the institutions of 97.2% of respondents. A total of 78/108 (72.2%) described themselves as "comfortable" or "very comfortable" in pediatric VAD management. While 63% (68/108) of respondents reported that they had never performed (or overseen the performance of) chest compressions in a pediatric patient with a VAD, 37% (40/108) reported performing CPR at least once in a VAD patient. Conclusion : With no existing international guidelines for emergency cardiovascular care in the pediatric VAD population, our survey identifies an important gap in resuscitation recommendations., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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- 2024
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18. Staged vs Complete Repair in Tetralogy of Fallot With Pulmonary Atresia.
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Boucek K, Mastropietro CW, Beall J, Keller E, Beshish A, Flores S, Chlebowski M, Yates AR, Choudhury TA, Mueller D, Kwiatkowski DM, Migally K, Karki K, Willett R, Radman MR, Reddy C, Piggott K, Capone CA, Kapileshwarkar Y, Vijayakumar N, Prentice E, Narasimhulu SS, Martin RH, and Costello JM
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- Infant, Humans, Retrospective Studies, Treatment Outcome, Pulmonary Artery surgery, Pulmonary Artery abnormalities, Tetralogy of Fallot complications, Pulmonary Atresia, Cardiac Surgical Procedures methods
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Background: We sought to compare outcomes for infants with tetralogy of Fallot with pulmonary atresia (TOF/PA) and confluent pulmonary arteries who underwent staged or primary complete surgical repair., Methods: This retrospective study included infants undergoing initial surgical intervention between 0 and 60 days of age with TOF/PA without aortopulmonary collaterals from 2009 to 2018 at 20 centers. The primary outcome was days alive and out of the hospital in the first year of life (DAOH365). Secondary outcomes were mortality at 1 year of age and a composite major complication outcome. Multivariable modeling with generalized estimating equations were used to compare outcomes between groups., Results: Of 221 subjects, 142 underwent staged repair and 79 underwent primary complete repair. There was no significant difference in median DAOH365 between the staged and primary repair groups (317 days [interquartile range, 278-336] vs 338 days [interquartile range, 314-348], respectively; adjusted P = .13). Nine staged repair patients (7%) died in the first year of life vs 5 primary repair patients (6%; adjusted odds ratio, 1.00; 95% CI, 0.25-3.95). At least 1 major complication occurred in 37% of patients who underwent staged repair vs 41% of patients who underwent primary complete repair (P = .75), largely driven by the need for unplanned cardiac reinterventions., Conclusions: For infants with TOF/PA with confluent pulmonary arteries, a surgical strategy of staged or primary complete repair resulted in statistically similar DAOH365, early mortality, and morbidity., (Published by Elsevier Inc.)
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- 2023
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19. Elevated cardiac biomarkers and outcomes in children and adolescents with acute COVID-19.
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Fremed MA, Healy EW, Choi NH, Cheung EW, Choudhury TA, Jiang P, Liberman L, Zucker J, Lytrivi ID, and Starc TJ
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- Humans, Child, Adolescent, Retrospective Studies, SARS-CoV-2, Cohort Studies, Biomarkers, Natriuretic Peptide, Brain, COVID-19 epidemiology
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Cardiac involvement associated with multi-system inflammatory syndrome in children has been extensively reported, but the prevalence of cardiac involvement in children with SARS-CoV-2 infection in the absence of inflammatory syndrome has not been well described. In this retrospective, single centre, cohort study, we describe the cardiac involvement found in this population and report on outcomes of patients with and without elevated cardiac biomarkers. Those with multi-system inflammatory syndrome in children, cardiomyopathy, or complex CHD were excluded. Inclusion criteriaz were met by 80 patients during the initial peak of the pandemic at our institution. High-sensitivity troponin T and/or N-terminal pro-brain type natriuretic peptide were measured in 27/80 (34%) patients and abnormalities were present in 5/27 (19%), all of whom had underlying comorbidities. Advanced respiratory support was required in all patients with elevated cardiac biomarkers. Electrocardiographic abnormalities were identified in 14/38 (37%) studies. Echocardiograms were performed on 7/80 patients, and none demonstrated left ventricular dysfunction. Larger studies to determine the true extent of cardiac involvement in children with COVID-19 would be useful to guide recommendations for standard workup and management.
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- 2023
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20. Post-operative troponin levels and left ventricular function in patients with d-transposition of the great arteries following the arterial switch operation.
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Ro SS, Wan Q, Pasumarti N, Keelan J, Shah A, Krishnamurthy G, Choudhury TA, Anderson BR, LaPar D, Bacha E, and DiLorenzo MP
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- Humans, Infant, Newborn, Arteries, Predictive Value of Tests, Treatment Outcome, Troponin I, Troponin T, Ventricular Function, Left, Arterial Switch Operation, Transposition of Great Vessels diagnostic imaging, Transposition of Great Vessels surgery, Ventricular Dysfunction, Left diagnostic imaging, Ventricular Dysfunction, Left etiology
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The aim of this study was to assess the significance of post-operative troponin levels as a surrogate for left ventricular (LV) dysfunction measured by global longitudinal strain (GLS) in patients with dextro-transposition of the great arteries (d-TGA) who undergo an arterial switch operation (ASO), and to explore the LV GLS recovery in the mid-term follow-up period. Seventy-eight neonates were included, of whom 41 had troponin-I measurements and 37 had troponin-T measurements. The primary outcome of LV GLS was assessed and compared with healthy controls at the pre-operative stage and time of discharge, 3 months, 6 months and 12 months of age. Secondary outcomes included deaths or transplantations and other clinical markers such as length of hospital stay. D-TGA patients had worse LV GLS post-operatively compared to age-matched controls (p < 0.01) which improved by 12 months of age (p = 0.53). No association was found between changes in troponin-I or troponin-T levels and LV GLS at the time of discharge (r = 0.4, p = 0.64 and r = -0.5, p = 0.91, respectively). In addition, there were no deaths or transplantations in this cohort over a period of 12 months. LV GLS appears to worsen in the early post-operative period for d-TGA patients who undergo neonatal ASO but this recovers through the first post-operative year. Troponin levels have limited value in predicting early or midterm LV dysfunction and recovery., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)
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- 2023
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21. The nucleolar δ isoform of adapter protein SH2B1 enhances morphological complexity and function of cultured neurons.
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Cote JL, Vander PB, Ellis M, Cline JM, Svezhova N, Doche ME, Maures TJ, Choudhury TA, Kong S, Klaft OGJ, Joe RM, Argetsinger LS, and Carter-Su C
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- Adaptor Proteins, Signal Transducing metabolism, Animals, Brain-Derived Neurotrophic Factor genetics, Brain-Derived Neurotrophic Factor metabolism, Cells, Cultured, Mice, Neurites metabolism, Neurons metabolism, Protein Isoforms genetics, Protein Isoforms metabolism, Adaptor Proteins, Signal Transducing genetics, Neurons cytology
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The adapter protein SH2B1 is recruited to neurotrophin receptors, including TrkB (also known as NTRK2), the receptor for brain-derived neurotrophic factor (BDNF). Herein, we demonstrate that the four alternatively spliced isoforms of SH2B1 (SH2B1α-SH2B1δ) are important determinants of neuronal architecture and neurotrophin-induced gene expression. Primary hippocampal neurons from Sh2b1-/- [knockout (KO)] mice exhibit decreased neurite complexity and length, and BDNF-induced expression of the synapse-related immediate early genes Egr1 and Arc. Reintroduction of each SH2B1 isoform into KO neurons increases neurite complexity; the brain-specific δ isoform also increases total neurite length. Human obesity-associated variants, when expressed in SH2B1δ, alter neurite complexity, suggesting that a decrease or increase in neurite branching may have deleterious effects that contribute to the severe childhood obesity and neurobehavioral abnormalities associated with these variants. Surprisingly, in contrast to SH2B1α, SH2B1β and SH2B1γ, which localize primarily in the cytoplasm and plasma membrane, SH2B1δ resides primarily in nucleoli. Some SH2B1δ is also present in the plasma membrane and nucleus. Nucleolar localization, driven by two highly basic regions unique to SH2B1δ, is required for SH2B1δ to maximally increase neurite complexity and BDNF-induced expression of Egr1, Arc and FosL1., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2022. Published by The Company of Biologists Ltd.)
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- 2022
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22. Left Heart Decompression on Veno-Arterial Extracorporeal Membrane Oxygenation in Children With Dilated Cardiomyopathy and Myocarditis: An Extracorporeal Life Support Organization Registry Review.
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Choudhury TA, Ofori-Amanfo G, Choi J, Eisenberg RE, Rycus P, Medar SS, and Aydin SI
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- Child, Decompression, Humans, Infant, Registries, Retrospective Studies, Time Factors, Cardiomyopathy, Dilated complications, Cardiomyopathy, Dilated therapy, Extracorporeal Membrane Oxygenation, Myocarditis complications, Myocarditis diagnosis, Myocarditis therapy
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Objectives: To describe the association between left heart decompression on veno-arterial extracorporeal membrane oxygenation and survival in patients with myocarditis and dilated cardiomyopathy. The secondary outcome is to study association of left heart decompression with survival in children with myocarditis compared with those with dilated cardiomyopathy., Design: Retrospective study of a multicenter registry database., Setting: Data reported to Extracorporeal Life Support Organization from international extracorporeal membrane oxygenation centers., Patients: Patients less than or equal to 18 years old with a diagnosis of myocarditis or dilated cardiomyopathy receiving extracorporeal membrane oxygenation., Interventions: None., Measurements and Main Results: A total of 1,438 pediatric extracorporeal membrane oxygenation runs were identified. Thirty-seven percent of the patients had myocarditis (n = 532), whereas the rest had dilated cardiomyopathy. Survival to hospital discharge was 63%. Median extracorporeal membrane oxygenation duration was 148 hours with interquartile range (84-248 hr). Nineteen percent of patients (n = 274) had left heart decompression. Multivariable analysis revealed using left heart decompression (adjusted odds ratio, 1.42; 95% CI, 1.06-1.89; p = 0.02), e-cardiopulmonary resuscitation (adjusted odds ratio, 0.63; 95% CI, 0.51-0.79; p < 0.001), higher pH (adjusted odds ratio, 3.69; 95% CI, 1.80-7.53; p < 0.001), and diagnosis of myocarditis (adjusted odds ratio, 1.69; 95% CI, 1.35-2.08; p < 0.001) were associated with greater odds of survival. In the multivariable analysis for patients with dilated cardiomyopathy, left heart decompression failed to reveal a significant association with survival (20% among survivors vs 17% among nonsurvivors, 95% CI, -2.2% to 8.0%). Meanwhile in patients with myocarditis, the multivariable analysis failed to exclude the possibility that left heart decompression was associated with up to a three-fold greater odds of survival (adjusted odds ratio, 1.77; 95% CI, 0.99-.15)., Conclusions: Retrospective review of the Extracorporeal Life Support Organization registry revealed an association between left heart decompression and greater odds of survival in children with myocarditis and dilated cardiomyopathy on extracorporeal membrane oxygenation. When comparing patients with dilated cardiomyopathy against those with myocarditis, we could not exclude a three-fold greater odds of survival associated with the use of left heart decompression. This finding warrants further prospective evaluation., Competing Interests: The authors have disclosed that they do not have any potential conflicts of interest., (Copyright © 2021 by the Society of Critical Care Medicine and the World Federation of Pediatric Intensive and Critical Care Societies.)
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- 2021
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23. Early Thromboprophylaxis Initiation is Associated With Reduced Fontan Thromboses in the Early Postoperative Period.
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Ankola AA, Anderson BR, Choudhury TA, Rochelson E, Corda R, Bacha EA, and Smerling AJ
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- Anticoagulants, Child, Humans, Postoperative Complications epidemiology, Postoperative Complications etiology, Postoperative Complications prevention & control, Postoperative Period, Warfarin, Thrombosis diagnostic imaging, Thrombosis epidemiology, Thrombosis etiology, Venous Thromboembolism
- Abstract
Fontan circuit thrombosis is a significant cause of early postoperative morbidity and mortality. Thrombosis incidence and relationship to thromboprophylaxis choice and timing of initiation are not well established. We sought to evaluate the incidence of Fontan circuit thrombosis in the first 30 postoperative days and its relationship to thromboprophylaxis choice and timing. Patients undergoing Fontan surgery, 2006-2016, were reviewed. Fontan circuit thrombosis was defined by sonographic detection of intracardiac or deep venous thrombi. Logistic regression was used to assess relationships between thromboprophylaxis characteristics and thrombosis. One hundred ninety-two patients underwent Fontan. Fontan thrombosis occurred in 19 (10%) patients. 54% were started on aspirin, 27% coumadin, 4% heparin, and 7% none. There was no relationship between thrombosis and baseline anatomy, Fontan type or fenestration. Median time to thromboprophylaxis initiation was 4 days (interquartile range 2-6). Patients not started on thromboprophylaxis had 44.8 times the odds of thrombosis as those on thromboprophylaxis (confidence interval 6.4-311.7, P < 0.01); no children starting thromboprophylaxis before postoperative day 2 developed thromboses. For every day that thromboprophylaxis was delayed, odds of thrombosis increased by 30% (odds ratio 1.3; CI 1.1-1.6, P < 0.01). There was no difference in the odds of thrombosis between children taking aspirin vs other thromboprophylaxis types. Odds of early postoperative Fontan circuit thrombosis are increased in patients in whom thromboprophylaxis is delayed beyond the second postoperative day, with no difference in the odds of thrombosis between patients initiated on aspirin vs other thromboprophylaxis. Early aspirin institution post Fontan is recommended to reduce morbidity. Ultra-mini-Abstract: Odds of early postoperative Fontan circuit thrombosis are increased in patients in whom thromboprophylaxis is delayed beyond the second postoperative day, with no difference in the odds of thrombosis between patients initiated on aspirin vs other thromboprophylaxis. Early aspirin institution post Fontan is recommended to reduce morbidity and resource utilization., (Copyright © 2021 Elsevier Inc. All rights reserved.)
- Published
- 2021
- Full Text
- View/download PDF
24. Simulation as an Educational Tool in the Pediatric Cardiac Intensive Care Unit.
- Author
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Choudhury TA, Flyer JN, and McBride ME
- Abstract
Purpose of Review: This review highlights the use of simulation as an educational tool in the highly specialized pediatric cardiac intensive care unit (PCICU)., Recent Findings: Healthcare simulation is used in high acuity medical environments to test healthcare systems. Healthcare simulation can improve team training, patient safety, and improve medical decision-making. Complex physiologies in the PCICU demand effective teamwork to consistently deliver high-quality patient care. Simulation-based PCICU learning objectives depend on a structured cognitive load framework to account for individual learner abilities, team constructs, and healthcare resources., Summary: PCICU simulation programs are strengthened by utilizing traditional education theory, with careful consideration of complex physiologies, interprofessional personnel, and center-specific resources. Virtual platforms should continue to evolve to provide additional, more convenient venues for individual learners and teams. Healthcare systems should frequently intersect with simulation educators to create relevant learning objectives that will contribute to patient safety, improve team performance, and patient outcomes., (© The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature 2021.)
- Published
- 2021
- Full Text
- View/download PDF
25. Cardiac workup and monitoring in hospitalised children with COVID- 19.
- Author
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Fremed MA, Lytrivi ID, Liberman L, Anderson BR, Barry OM, Choudhury TA, Chrisomalis-Dring S, Ferris A, Glickstein JS, Krishnan U, Levasseur S, Rosenzweig EB, Shah A, Silver ES, Suh S, Turner ME, Weller R, Woo J, and Starc TJ
- Subjects
- COVID-19, Child, Hospitalization, Humans, Pandemics, SARS-CoV-2, Betacoronavirus, Coronavirus Infections complications, Heart Diseases diagnosis, Heart Diseases virology, Pneumonia, Viral complications
- Abstract
Approximately, 1.7 million individuals in the United States have been infected with SARS-CoV-2, the virus responsible for the novel coronavirus disease-2019 (COVID-19). This has disproportionately impacted adults, but many children have been infected and hospitalised as well. To date, there is not much information published addressing the cardiac workup and monitoring of children with COVID-19. Here, we share the approach to the cardiac workup and monitoring utilised at a large congenital heart centre in New York City, the epicentre of the COVID-19 pandemic in the United States.
- Published
- 2020
- Full Text
- View/download PDF
26. A Case of Mitral Valve Endocarditis Complicated by Multiple Embolic Phenomena: Leaping from Adult Guidelines to Pediatric Critical Care Decisions.
- Author
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Choudhury TA, Flyer JN, Ushay HM, and Ofori-Amanfo G
- Abstract
Early surgical intervention for children with infective endocarditis (IE) and cerebrovascular sequelae has significant risks, resulting in practice variation amongst pediatric cardiologists, intensivists, and cardiothoracic surgeons. The limited pediatric consensus recommendations make decision making for practitioners challenging. The added risk of multiorgan dysfunction syndrome can make these decisions even more difficult. We present the case of a 14-year-old with IE and resultant multiorgan dysfunction syndrome including cerebrovascular complication, successfully treated by primary valve repair within the 1st week of diagnosis.
- Published
- 2019
- Full Text
- View/download PDF
27. Disseminated Histoplasmosis presenting as oropharyngeal mass lesion.
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Choudhury TA, Baruah R, Shah N, Lahkar B, Ahmed K, and Sarmah BJ
- Abstract
A 62 year old man from Silchar in North East India presented with complaints of painful swallowing, hoarseness, fever, anorexia and weight loss. Oropharyngeal examination revealed reddish ulcero-nodular lesion involving left tonsillar area and base of tongue which was clinically suspicious of malignancy. Radiological examination revealed involvement of bilateral adrenals by a mass. The biopsy of the oropharyngeal lesion showed many fungal spores morphologically favoring Histoplasmosis. Treatment with Amphotericin B followed by Itraconazole resulted recovery of lesions.
- Published
- 2019
- Full Text
- View/download PDF
28. Lab-on-a-chip workshop activities for secondary school students.
- Author
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Esfahani MM, Tarn MD, Choudhury TA, Hewitt LC, Mayo AJ, Rubin TA, Waller MR, Christensen MG, Dawson A, and Pamme N
- Abstract
The ability to engage and inspire younger generations in novel areas of science is important for bringing new researchers into a burgeoning field, such as lab-on-a-chip. We recently held a lab-on-a-chip workshop for secondary school students, for which we developed a number of hands-on activities that explained various aspects of microfluidic technology, including fabrication (milling and moulding of microfluidic devices, and wax printing of microfluidic paper-based analytical devices, so-called μPADs), flow regimes (gradient formation via diffusive mixing), and applications (tissue analysis and μPADs). Questionnaires completed by the students indicated that they found the workshop both interesting and informative, with all activities proving successful, while providing feedback that could be incorporated into later iterations of the event.
- Published
- 2016
- Full Text
- View/download PDF
29. Rhabdomyolysis Induced Acute Renal Failure: A Rare Complication of Falciparum Malaria.
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Prabhakar, Rathore SS, Choudhury TA, Kishan A, Gupta T, and Prakash J
- Subjects
- Acute Kidney Injury therapy, Adult, Antimalarials therapeutic use, Humans, Malaria, Falciparum drug therapy, Male, Renal Dialysis, Rhabdomyolysis drug therapy, Young Adult, Acute Kidney Injury etiology, Malaria, Falciparum complications, Rhabdomyolysis complications
- Published
- 2014
30. Clinicopathologic spectrum of crescentic glomerulonephritis: a hospital-based study.
- Author
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Choudhury TA, Singh RG, Singh S, Singh TB, and Rathore SS
- Subjects
- Adolescent, Adult, Aged, Antibodies, Antineutrophil Cytoplasmic blood, Antibodies, Antinuclear blood, Autoantibodies blood, Biomarkers blood, Biopsy, Child, Disease Progression, Female, Fibrosis, Glomerulonephritis immunology, Glomerulonephritis mortality, Glomerulonephritis therapy, Humans, Incidence, India epidemiology, Kidney Failure, Chronic mortality, Kidney Failure, Chronic pathology, Kidney Glomerulus immunology, Lupus Nephritis mortality, Lupus Nephritis pathology, Male, Middle Aged, Nephrotic Syndrome mortality, Nephrotic Syndrome pathology, Predictive Value of Tests, Remission Induction, Renal Dialysis, Retrospective Studies, Tertiary Care Centers, Time Factors, Treatment Outcome, Young Adult, Glomerulonephritis pathology, Kidney Glomerulus pathology
- Abstract
Recent data regarding the clinical and histopathologic spectrum of crescentic glomerulonephritis (CSGN) among the Indian adult population is unknown. Our aim is to study the clinicopathological features and outcome of CSGN. It is a retrospective observational study from a tertiary care hospital in India over 3.5 years. Biopsy-proven cases of CSGN (i.e., >50% crescents in glomeruli) were included in the study. Cases with insufficient data were excluded. There were 34 cases of CSGN, accounting for an incidence of 5.5% among kidney biopsies. The mean age was 32.2 ± 16.09 years, with male to female ratio of 12:22. Clinical presentations of CSGN include rapidly progressive glomerulonephritis in 23 (67.7%), chronic renal failure (CRF) in seven (20.5%), nephrotic syndrome in two (5.8%) and acute nephritic syndrome in two (5.8%) patients. The immunological profile of CSGN showed MPO-ANCA in nine (26.4%), PR3-ANCA in one (2.9%), both PR3 and MPO-ANCA in one (2.9%), anti-GBM antibody in five (14.7%) and lupus nephritis in six (17.6%) patients. All the three antibodies were present in one patient. The percentage of glomeruli showing crescents were 100% in nine (26.4%) and ≥80% in seven (20.5%) patients. Type of crescents seen were cellular in 11 (32.3%) and fibrocellular in 22 (64.7%) patients and fibrous in one (2.9%) patient. Interstitial fibrosis was found in seven (20.5%) patients. Dialysis dependency was seen in 11 (32.3%) patients. After 3 months of follow-up, mortality was seen in three (8.8%), remission in eight (23.5%), CRF in 15 (44.1%) and ESRD in five (14.7%) patients. CSGN carries a poor prognosis. The disorder may have an insidious onset and a slowly progressive course. ANCA, anti-GBM-antibody and anti-dsDNA can coexist in CSGN.
- Published
- 2014
- Full Text
- View/download PDF
31. Subclavian artery- internal jugular vein fistula and heart failure: complication of internal jugular vein catheterization.
- Author
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Prakash J, Takhellambam B, Ghosh B, Choudhury TA, Singh S, and Sharma OP
- Subjects
- Angiography, Arteriovenous Fistula diagnostic imaging, Female, Humans, Kidney Failure, Chronic complications, Kidney Failure, Chronic therapy, Middle Aged, Renal Dialysis, Tomography, X-Ray Computed, Ultrasonography, Doppler, Color, Arteriovenous Fistula etiology, Catheterization, Central Venous adverse effects, Heart Failure etiology, Jugular Veins diagnostic imaging, Subclavian Artery diagnostic imaging
- Abstract
Hemodialysis in patients with end-stage renal disease (ESRD) requires vascular access which can be either temporary or permanent. However, these procedures are not without complications. Arterial puncture is the most common immediate complication and pseudoaneurysm formation is the most common late sequel of internal jugular venous catheterization (IJVC). However, arterio-venous fistula (AVF) formatiorn following IJVC is rare. We are reporting a case of AVF formation between subclavian artery (SCA) and internal jugular vein (IJV) following IJVC which later on leads to the development of cardiac failure.
- Published
- 2013
32. The changing pattern of renal amyloidosis in Indian subcontinent: two decades of experience from a single center.
- Author
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Prakash J, Brojen T, Rathore SS, Choudhury TA, and Gupta T
- Subjects
- Adolescent, Adult, Aged, Female, Humans, India, Male, Middle Aged, Retrospective Studies, Time Factors, Young Adult, Amyloidosis diagnosis, Amyloidosis epidemiology, Kidney Diseases diagnosis, Kidney Diseases epidemiology
- Abstract
Background: Renal amyloidosis is a major cause of morbidity and mortality among the patients of systemic amyloidosis. The causes of amyloidosis vary from country to country and from time to time at individual center., Aim: This study investigates the changes in epidemiological and clinical profile of renal amyloidosis in recent years., Method: Cases of biopsy-proven renal amyloidosis from January 1992 to December 2010 were studied retrospectively. They were divided into two groups: 1990s (between 1992 and 2002) and 2000s (between 2003 and 2010). The clinical characteristics of patients were studied and compared between the groups., Result: A total of 2498 (974 in 1990s and 1524 in 2000s) renal biopsies was done during the 19-year period. The incidence of amyloidosis in 1990s and 2000s was 1.74% (n = 17) and 1.9% (n = 29), respectively (p > 0.05). We noted that the incidence of renal amyloidosis increased significantly (p < 0.05) among the females in 2000s. The mean age of patients in 2000s and 1990s was 38 ± 17.9 and 39.2 ± 19 years, respectively (p = 0.83). Renal insufficiency in patients with renal amyloidosis significantly increased (p < 0.05) in 2000s (n = 14; 48.2%) in comparison to 1990s (n = 2; 12.8%). Subnephrotic proteinuria was observed in 12.8% (n = 2) and 48.82% (n = 14) of patients in 1990s and 2000s, respectively (p < 0.05). Infection (n = 10; 58.8%) was the most common cause of secondary amyloidosis during the 1990s, whereas chronic inflammation (n = 14; 48.2%) was the most common cause in 2000s. In 1990s, the incidence of ankylosing spondylitis (AS) and rheumatoid arthritis (RA) was 11.7% (n = 2) and 5.8% (n = 1), respectively, but in 2000s, their respective incidence was 17.2% (n = 5) each. Multiple myeloma (MM) was the most common cause of amyloid light chain protein (AL) amyloidosis in both the groups. We observed systemic lupus erythromatosus (SLE)-related renal amyloidosis in two cases and Hodgkin lymphoma-associated amyloidosis in one case in 2000s., Conclusion: The overall incidence of renal amyloidosis showed little change from 1990s to 2000s. Chronic inflammatory diseases were the most common cause of renal amyloidosis in 2000s in contrast to infections in 1990s. Female gender was more affected in 2000s than in 1990s. Renal insufficiency and subnephrotic-range proteinuria were more frequent clinical manifestations of renal amyloidosis in recent years (2000s) in comparison to the earlier decade (1990s).
- Published
- 2012
- Full Text
- View/download PDF
33. Angiotensin II receptor gene polymorphisms and risk of myocardial infarction.
- Author
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Choudhury TA, Dronsfield MJ, Jones AF, and Bain SC
- Subjects
- Genotype, Humans, Risk, Myocardial Infarction genetics, Peptidyl-Dipeptidase A genetics, Polymorphism, Genetic, Receptors, Angiotensin genetics
- Published
- 1994
- Full Text
- View/download PDF
34. Relationship between the depletion of O6-methylguanine-DNA methyltransferase by O6-methylguanine and the stimulation of DNA synthesis and growth of cultured chick hepatocytes.
- Author
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Dutta-Choudhury TA, Couri D, and Stephens RE
- Subjects
- Animals, Cell Division, Cells, Cultured, Chick Embryo, Guanine pharmacology, Liver cytology, Methyltransferases analysis, O(6)-Methylguanine-DNA Methyltransferase, DNA biosynthesis, Guanine analogs & derivatives, Liver metabolism, Methyltransferases physiology
- Abstract
O6-Methylguanine-DNA methyltransferase (O6-MT) has been described as a DNA repair enzyme that reverses alkylation damage at the O6 position of guanine in DNA. We demonstrate that the concentration of this protein decreases immediately prior to DNA synthesis in cultured chick hepatocytes. If intracellular levels are experimentally depleted by treatment of cultures with O6-methylguanine, DNA synthesis occurs as an associated resultant. This effect is dose dependent and can be followed by discernible morphological changes of organoids in culture. Increased and altered growth caused by O6-methylguanine was quantified and was also found to be dose dependent. Therefore, O6-MT may play a role in the regulation of DNA synthesis.
- Published
- 1992
- Full Text
- View/download PDF
35. Cellular levels of O6-methylguanine-DNA methyltransferase in mammary epithelial cells and liver from virgin, pregnant and pituitary grafted mice.
- Author
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Dutta-Choudhury TA, Bak BH, and Guzman RC
- Subjects
- Animals, Colonic Neoplasms enzymology, Colonic Neoplasms pathology, Epithelial Cells, Epithelium enzymology, Estrus metabolism, Female, Liver cytology, Mice, Mice, Inbred BALB C, O(6)-Methylguanine-DNA Methyltransferase, Pituitary Gland physiology, Pituitary Gland transplantation, Pregnancy, Tumor Cells, Cultured enzymology, Liver enzymology, Mammary Glands, Animal enzymology, Methyltransferases metabolism, Pregnancy, Animal metabolism
- Abstract
O6-Methylguanine-DNA methyltransferase (O6-MT) is a DNA repair protein that reverses alkylation damage at the O6 position of guanine. In the process, O6-MT undergoes suicide inactivation. To determine if this enzyme might be regulated by pregnancy-associated hormones we measured changes in the level of O6-MT in isolated mouse mammary epithelial cell homogenates during different reproductive states. These were pregnancy, ectopic pituitary transplantation, proestrus/estrus and diestrus. O6-MT levels were found to be similar in mice in proestrus/estrus (0.95 fmol/micrograms DNA) as compared to diestrus (0.94 fmol/micrograms DNA) and also mixed populations of virgin mice (1.09 fmol/micrograms DNA). A mean for all virgin mice (0.97 fmol/micrograms DNA) was used as a comparative index. O6-MT decreased 2-fold during pregnancy in mammary epithelial cells to a mean value of 0.45 fmol/micrograms DNA (P less than 0.05). A smaller decrease (0.65 fmol/micrograms DNA; P less than 0.01) in mammary epithelial cells was found at 3 weeks following pituitary isograft. The repair capacity of mammary epithelial cells to liver was compared by measurements made in liver homogenates from the same mice and are approximately 3-fold higher in liver from virgin mice (3.2 fmol/micrograms DNA) than mammary gland. Liver levels of O6-MT increased in pregnant (5.3 fmol/micrograms DNA) and pituitary transplanted (3.9 fmol/micrograms DNA) mice, and were 5- and 4-fold higher than the concentration in virgin mammary epithelial cells respectively.
- Published
- 1991
- Full Text
- View/download PDF
36. Human erythrocyte acetylcholinesterase is an amphipathic protein whose short membrane-binding domain is removed by papain digestion.
- Author
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Dutta-Choudhury TA and Rosenberry TL
- Subjects
- Binding Sites, Endopeptidases pharmacology, Humans, Macromolecular Substances, Molecular Weight, Papain pharmacology, Protein Binding, Acetylcholinesterase blood, Erythrocyte Membrane enzymology
- Abstract
Human erythrocyte acetylcholinesterase was shown to be an amphipathic protein in which proteases could cleave the hydrophobic domain from the enzymatically active hydrophilic domain. Papain and Pronase cleaved these domains with greatest efficiency, as measured by the disaggregation of purified acetylcholinesterase to disulfide-linked dimers (G2) on sucrose density gradients in the absence of detergent. Nonspecific proteolytic degradation was reduced both by the inclusion of edrophonium chloride, which protected acetylcholinesterase from inactivation, and by covalent attachment of papain to Sepharose CL-4B. In contrast to nondigested control acetylcholinesterase, the papain-disaggregated enzyme did not bind detergent according to hydrodynamic criteria and could not be reconstituted into liposomes. Thus, we conclude that the hydrophobic domain removed by papain digestion is in fact the membrane-binding domain in situ. This domain appeared largely inaccessible to proteases in intact erythrocytes, however, as less than 10% of the enzyme activity was solubilized by protease digestion. The hydrophobic domain removed by papain appeared very small, as nondigested control and disaggregated enzyme were identical in molecular weight and amino acid composition within experimental error. The fully reduced 75-kDa catalytic subunits of nondigested control enzyme appeared about 2 kDa larger than the corresponding subunits of disaggregated enzyme on polyacrylamide gel electrophoresis in sodium dodecyl sulfate, an indication that the hydrophobic domain was cleaved from the COOH or NH2 terminus of the catalytic subunit primary structure. Studies in which the NH-terminal amino acid was labeled by reductive methylation suggested that the hydrophobic domain is at the COOH terminus.
- Published
- 1984
37. O6-methylguanine-DNA methyltransferase in human fetal tissues: fetal and maternal factors.
- Author
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D'Ambrosio SM, Samuel MJ, Dutta-Choudhury TA, and Wani AA
- Subjects
- Black People, Down Syndrome enzymology, Female, Gestational Age, Humans, Liver enzymology, O(6)-Methylguanine-DNA Methyltransferase, Pregnancy, Renal Dialysis, Smoking, White People, Fetus enzymology, Methyltransferases analysis
- Abstract
O6-Methylguanine methyltransferase (O6-MT) was measured and compared in extracts of 7 human fetal tissues obtained from 21 different fetal specimens as a function of fetal age and race and of maternal smoking and drug usage. Liver exhibited the highest activity followed by kidney, lung, small intestine, large intestine, skin, and brain. Each fetal organ homogenate exhibited a 3- to 5-fold level of interindividual variation of O6-MT. There did not appear to be any significant differences of O6-MT as a function of fetal race and age and in the tissues obtained from mothers who smoked cigarettes during pregnancy. The fetal tissues obtained from an individual using phenobarbital exhibited 4-fold increases in O6-MT activity. The tissues obtained from another individual on kidney dialysis were 2- to 3-fold higher than the normal population. These data suggest a possible enhancement of human fetal O6-MT by certain xenobiotics, with little if any modulation by racial factors and maternal smoking habits.
- Published
- 1987
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