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Chowdhury S, Crocker NA, Peebles WA, Rhodes TL, Zeng L, Lantsov R, Van Compernolle B, Brookman M, Pinsker RI, Lau C. A novel Doppler backscattering (DBS) system to simultaneously measure radio frequency plasma fluctuations and low frequency turbulence. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:073504. [PMID: 37493501 DOI: 10.1063/5.0149654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 07/12/2023] [Indexed: 07/27/2023]
Abstract
A novel quadrature Doppler Backscattering (DBS) system has been developed and optimized for the E-band (60-90 GHz) frequency range using either O-mode or X-mode polarization in DIII-D plasmas. In general, DBS measures the amplitude of density fluctuations and their velocity in the lab frame. The system can simultaneously monitor both low-frequency turbulence (f < 10 MHz) and radiofrequency plasma density fluctuations over a selectable frequency range (20-500 MHz). Detection of high-frequency fluctuations has been demonstrated for low harmonics of the ion cyclotron frequency (e.g., 2fci ∼ 23 MHz) and externally driven high-frequency helicon waves (f = 476 MHz) using an adjustable frequency down conversion system. Importantly, this extends the application of DBS to a high-frequency spectral domain while maintaining important turbulence and flow measurement capabilities. This unique system has low phase noise, good temporal resolution (sub-millisecond), and excellent wavenumber coverage (kθ ∼ 1-20 cm-1 and kr ≲ 30 cm-1). As a demonstration, localized internal DIII-D plasma measurements are presented from turbulence (f ≤ 5 MHz), Alfvenic waves (f ∼ 6.5 MHz), ion cyclotron waves (f ≥ 20 MHz), as well as fluctuations around 476 MHz driven by an external high-power 476 MHz helicon wave antenna. In the future, helicon measurements will be used to validate GENRAY and AORSA modeling tools for prediction of helicon wave propagation, absorption, and current drive location for the newly installed helicon current drive system on DIII-D.
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Lau C, Zhu X, Chan WY. Automatic depression severity assessment with deep learning using parameter-efficient tuning. Front Psychiatry 2023; 14:1160291. [PMID: 37398577 PMCID: PMC10308283 DOI: 10.3389/fpsyt.2023.1160291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 06/01/2023] [Indexed: 07/04/2023] Open
Abstract
Introduction To assist mental health care providers with the assessment of depression, research to develop a standardized, accessible, and non-invasive technique has garnered considerable attention. Our study focuses on the application of deep learning models for automatic assessment of depression severity based on clinical interview transcriptions. Despite the recent success of deep learning, the lack of large-scale high-quality datasets is a major performance bottleneck for many mental health applications. Methods A novel approach is proposed to address the data scarcity problem for depression assessment. It leverages both pretrained large language models and parameter-efficient tuning techniques. The approach is built upon adapting a small set of tunable parameters, known as prefix vectors, to guide a pretrained model towards predicting the Patient Health Questionnaire (PHQ)-8 score of a person. Experiments were conducted on the Distress Analysis Interview Corpus - Wizard of Oz (DAIC-WOZ) benchmark dataset with 189 subjects, partitioned into training, development, and test sets. Model learning was done on the training set. Prediction performance mean and standard deviation of each model, with five randomly-initialized runs, were reported on the development set. Finally, optimized models were evaluated on the test set. Results The proposed model with prefix vectors outperformed all previously published methods, including models which utilized multiple types of data modalities, and achieved the best reported performance on the test set of DAIC-WOZ with a root mean square error of 4.67 and a mean absolute error of 3.80 on the PHQ-8 scale. Compared to conventionally fine-tuned baseline models, prefix-enhanced models were less prone to overfitting by using far fewer training parameters (<6% relatively). Discussion While transfer learning through pretrained large language models can provide a good starting point for downstream learning, prefix vectors can further adapt the pretrained models effectively to the depression assessment task by only adjusting a small number of parameters. The improvement is in part due to the fine-grain flexibility of prefix vector size in adjusting the model's learning capacity. Our results provide evidence that prefix-tuning can be a useful approach in developing tools for automatic depression assessment.
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Leppink E, Lau C, Lin Y, Wukitch SJ. Evaluation of the Abel inversion integral in O-mode plasma reflectometry using Chebyshev-Gauss quadrature. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:063506. [PMID: 37862546 DOI: 10.1063/5.0132246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Accepted: 06/15/2023] [Indexed: 10/22/2023]
Abstract
The Abel transform is often used to reconstruct plasma density profiles from O-Mode polarized reflectometry diagnostics. However, standard numerical trapezoidal evaluation of the Abel inversion integral can be computationally expensive for a large number of evaluation points, and an endpoint singularity exists on the upper-bound of the integral, which can result in an increased error. In this work, Chebyshev-Gauss quadrature is introduced as a new method to evaluate the Abel inversion integral for the problem of O-Mode plasma reflectometry. The method does not require numerical evaluation of an integral singularity and is shown to have similar accuracy compared to existing methods while being computationally efficient.
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Cerrato C, Margaret M, Autorino R, Simone G, Yang B, Uzzo R, Kutikov A, Porpiglia F, Capitanio U, Montorsi F, Porter J, Beksac A, Nguyen M, Hakimi K, Pandolfo S, Minervini A, Lau C, Monish A, Eun D, Mottrie A, Mir C, Sundaram C, Antonelli A, Kaouk J, Derweesh I. Partial versus radical nephrectomy for complex renal mass: Multicenter comparative analysis of functional outcomes (ROSULA Collaborative Group). Eur Urol 2023. [DOI: 10.1016/s0302-2838(23)01057-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Cerrato C, Autorino R, Simone G, Yang B, Uzzo R, Porpiglia F, Capitanio U, Montorsi F, Porter J, Beksac A, Minervini A, Lau C, Akbar A, Eun D, Mottrie A, Mir C, Meagher M, Nguyen M, Pandolfo S, Kutikov A, Cerruto M, Antonelli A, Sundaram C, Kaouk J, Derweesh I. Partial or radical nephrectomy for complex renal mass: A comparative analysis of oncological outcomes and complications from the rosula (robotic surgery for large renal mass) collaborative group. Eur Urol 2023. [DOI: 10.1016/s0302-2838(23)00891-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Zhang Y, Lau C, Gabriel B, Ifeoluwa J, Yap T. Venous thromboembolism risk in testosterone treated men with and without Klinefelter syndrome. Eur Urol 2023. [DOI: 10.1016/s0302-2838(23)00270-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/12/2023]
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Pasrija C, Shah A, Holmes S, Bittle G, Reed R, Patel V, Lau C, Krupnick A. Safety of Single Lung Transplantation Post Donation Service Area-Specific Organ Distribution. J Heart Lung Transplant 2022. [DOI: 10.1016/j.healun.2022.01.1226] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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Tuderti G, Autorino R, Minervini A, Kaouk J, Lau C, Perdonà S, Porpiglia F, Derweesh I, Saidian A, Nguyen M, Carbonara U, Rha K, Schiavina R, Mastroianni R, Misuraca L, Mari A, Brassetti A, Anceschi U, Bove A, Ferriero M, Mottrie A, Gallucci M, Simone G. On-clamp versus off-clamp robotic partial nephrectomy for totally endophytic deep renal masses: Propensity score-matched comparison of perioperative, oncologic and functional outcomes of a multicenter analysis (ROSULA database). Eur Urol 2022. [DOI: 10.1016/s0302-2838(22)00420-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Tuderti G, Autorino R, Mastroianni R, Mari A, Carbonara U, Misuraca L, Anceschi U, Brassetti A, Ferriero M, Bove A, Costantini M, Porpiglia F, Kaouk J, Lau C, Derweesh I, Rha K, Schiavina R, Mottrie A, Gallucci M, Simone G. Nephrometry scores predicting value of Trifecta achievement in a multicenter analysis (ROSULA database) of Robotic Partial Nephrectomy for totally endophytic “deep” renal masses. Eur Urol 2022. [DOI: 10.1016/s0302-2838(22)00146-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Lau C, Shabbir A, Rathod KS, Chhetri I, Ono M, Hamers AJP, Amarin JJ, Ibrahim A, Nuredini G, Godec T, Kapil V, Ahluwalia A. Inorganic nitrate attenuates endothelial dysfunction consequent to systemic inflammation. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.3008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Introduction
Chronic cardiovascular diseases are characterised by low-grade systemic inflammation and attenuated nitric oxide (NO) bioavailability resulting in endothelial dysfunction. Inorganic nitrate augments NO bioavailability and improves markers of vascular dysfunction in patients with cardiovascular risk factors. However, the exact mechanism of this effect is uncertain.
Purpose
To determine whether inorganic nitrate supplementation alters systemic inflammation-induced endothelial dysfunction.
Methods
62 healthy male volunteers were randomised 1:1 to receive ∼8–10 mmol of dietary inorganic nitrate in beetroot juice or nitrate-free beetroot juice (placebo) once daily for 6 days. Measures of brachial artery flow-mediated dilatation (FMD), brachial blood pressure (BP), pulse wave analysis and carotid-femoral pulse wave velocity (PWV) by Vicorder were taken prior to and at 8 hours after a typhoid vaccine (to induce mild systemic inflammation). Plasma, urine and saliva samples were also collected. Clinicaltrials.gov: NCT02715635.
Results
Baseline characteristics were similar between the two groups. Inorganic nitrate significantly elevated plasma nitrite (placebo = Δ0.02±0.5 μM, inorganic nitrate = Δ0.63±1.2 μM; p=0.01) and nitrate levels (p<0.0001) compared to placebo. There were significant increases in urine nitrite (p<0.0001) and nitrate (p<0.0001) in addition to salivary nitrite (p<0.0001) and nitrate (p<0.0001) compared to placebo. After 8 hours, typhoid vaccine induced an increase in circulating white cells (placebo = Δ3.34±3.37x109/L, inorganic nitrate = Δ2.9±2.78x109/L; p=0.58) that was similar in in both arms. However, there was a significant reduction in the FMD response in the placebo group at 8-hours post vaccine; an effect that was absent in volunteers treated with inorganic nitrate (placebo = Δ−1.33±1.53%, inorganic nitrate = Δ−0.07±1.84%, p=0.005). Importantly, there were no statistically significant differences in baseline vessel diameter (p=0.78), time to peak diameter in response to flow (p=0.87) and peak shear rate (p=0.57) between the groups. When comparing change from baseline to 8 hours after the vaccine, there were no significant differences in brachial systolic BP (p=0.12), central systolic BP (p=0.12) and PWV (p=0.60) between groups, but a significant reduction in brachial diastolic BP in the inorganic nitrate group (p=0.048).
Conclusions
Inflammation-induced endothelial dysfunction was prevented in those receiving dietary inorganic nitrate suggesting that elevating circulating nitrite and delivering NO to the blood vessel wall, through dietary approaches may offer potential therapeutic benefit in those cardiovascular diseases which typically exhibit low grade inflammation and deficiencies in bioavailable NO.
Funding Acknowledgement
Type of funding sources: Public Institution(s). Main funding source(s): British Heart Foundation
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Shabbir A, Lau C, Rathod KS, Chhetri I, Haque A, Godec T, Khambata RS, Kapil V, Ahluwalia A. Inorganic nitrate attenuates the systemic inflammatory response in typhoid vaccine-induced endothelial dysfunction in healthy volunteers. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.3009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Inflammatory responses underlie the development of endothelial dysfunction in CVD, however, therapeutics that might target this pathway have not been forthcoming. A key pathogenic mechanism mediating endothelial dysfunction is a reduction in bioavailable (eNOS-derived) nitric oxide (NO). Activation of the non-canonical pathway for in-vivo NO generation might offer an approach to improve NO levels and recover vascular function in pre-clinical models of CVD. Whether this might occur in humans is unknown.
Purpose
We hypothesize that consumption of inorganic nitrate will lead to increases in bioavailable NO and thus attenuate the inflammatory pathways leading to typhoid vaccine-induced endothelial dysfunction in healthy volunteers.
Methods
Healthy male volunteers were recruited (n=78) and randomized to receive either beetroot juice containing 8–10mmol nitrate or placebo (nitrate-deplete) juice once daily for 6 days. Participants underwent serial measurements of BP, FMD and GTN-induced brachial artery dilatation, and haematology and biochemistry, before and after typhoid vaccination. Blood, urine and saliva nitrite and nitrate were quantified using ozone chemiluminescence, and leukocyte flow cytometry analysis was conducted.
Results
8-hours post-vaccine endothelial function was depressed in placebo-treated volunteers, however this was prevented in nitrate-treated volunteers. This dysfunction was due to impaired endothelial function since responses to GTN were unaffected either by vaccination or dietary intervention (p=0.981). Dietary nitrate resulted in an increase in plasma (p<0.0001), urine (p=0.0006) and saliva (p<0.0001) nitrate, and urine (p=0.0354) and saliva (p<0.0001) nitrite levels. There was a reduction in the proportions of CD14++/CD16+intermediate monocytes in nitrate-treated participants after vaccine (p=0.016, change from baseline between groups). In the nitrate-treated group, less CD14++/CD16+ intermediate monocyte CD62L expression was identified post-vaccine (p=0.0122), compared to placebo, with no difference in soluble plasma CD62L between groups (p=0.875). CD11b median fluorescence intensity was increased in CD3+/CD4+ T-lymphocytes in nitrate-treated volunteers (p=0.0095).
Conclusions
Dietary nitrate reduced BP, as previously shown, indicating efficacy of the intervention. Importantly, we also now show for the first time that inorganic nitrate suppresses the systemic inflammatory response, specifically by reducing the numbers and activation state of CD14++/CD16+ intermediate monocytes. Furthermore, an increased expression of CD3+/CD4+ T-cell CD11b and preserved FMD in healthy volunteers treated with nitrate, suggests an anti-inflammatory phenotype, induced by the intervention, leading to improved endothelial function. Inorganic dietary nitrate modulates endothelial function through the attenuation of inflammatory responses and may be of potential therapeutic benefit in patients with established CAD.
Funding Acknowledgement
Type of funding sources: None.
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Misuraca L, Tuderti G, Autorino R, Carbonara U, Mari A, Amparore D, Mastroianni R, Bove A, Anceschi U, Ferriero M, Brassetti A, Perdonà S, Lau C, Koon H, Leonardo C, Schiavina R, Derweesh I, Porpiglia F, Mottrie A, Kaouk J, Minervini A, Simone G. Nephrometry scores predicting value of trifecta achievement in a multicenter analysis (ROSULA database) of robotic partial nephrectomy for totally endophytic “deep” renal masses. EUR UROL SUPPL 2021. [DOI: 10.1016/s2666-1683(21)00734-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Tuderti G, Autorino R, Carbonara U, Mari A, Amparore D, Mastroianni R, Bove A, Anceschi U, Perdonà S, Lau C, Koon H, Leonardo C, Misuraca L, Ferriero M, Brassetti A, Schiavina R, Derweesh I, Porpiglia F, Mottrie A, Kaouk J, Minervini A, Simone G. Renal function deterioration assessment in totally endophytic “deep” renal masses treated with robotic partial nephrectomy: comparison with a whole cohort of cT1-2 renal tumors patients from a multicenter analysis (ROSULA database). EUR UROL SUPPL 2021. [DOI: 10.1016/s2666-1683(21)00753-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Misuraca L, Tuderti G, Autorino R, Carbonara U, Mari A, Amparore D, Mastroianni R, Bove A, Anceschi U, Ferriero M, Brassetti A, Perdonà S, Lau C, Koon H, Leonardo C, Schiavina R, Derweesh I, Porpiglia F, Mottrie A, Kaouk J, Minervini A, Simone G. Robotic partial nephrectomy for totally endophytic “deep” renal masses: perioperative, pathologic, oncologic and functional outcomes of a multicenter analysis (ROSULA database). EUR UROL SUPPL 2021. [DOI: 10.1016/s2666-1683(21)00755-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Tuderti G, Autorino R, Carbonara U, Mari A, Amparore D, Mastroianni R, Bove A, Anceschi U, Misuraca L, Ferriero M, Brassetti A, Perdonà S, Lau C, Koon H, Leonardo C, Schiavina R, Derweesh I, Porpiglia F, Mottrie A, Kaouk J, Minervini A, Simone G. Trifecta assessment in totally endophytic “deep” renal masses treated with robotic partial nephrectomy: comparison with a whole cohort of cT1-2 renal tumors patients from a multicenter analysis (ROSULA database). EUR UROL SUPPL 2021. [DOI: 10.1016/s2666-1683(21)00754-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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Joy G, Artico J, Kurdi H, Lau C, Adam RD, Menacho KM, Pierce I, Captur G, Davies R, Schelbert EB, Fontana M, Kellman P, Treibel TA, Manisty C, Moon JC. Prospective case-control study of cardiovascular abnormalities six months following mild COVID-19 in healthcare workers. Eur Heart J Cardiovasc Imaging 2021. [PMCID: PMC8344927 DOI: 10.1093/ehjci/jeab090.064] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Public Institution(s). Main funding source(s): Barts Charity UCLH Charity
OnBehalf
COVIDsortium
Background
Recent CMR studies have reported cardiac abnormalities after COVID-19 are common, even after mild, non-hospitalised illness with evidence of ongoing myocardial inflammation. Such a prevalence of chronic myocarditis after mild disease has prompted societal concerns in diverse domains, and suggests that screening should be considered post COVID-19, even in asymptomatic individuals. Cardiovascular magnetic resonance (CMR) has proven utility for diagnosis in patients with COVID-19 infection and elevated troponin from unclear causes by measuring cardiac structure, function, myocardial scar (late gadolinium enhancement) and oedema (T1 and T2 mapping).
Objectives
We aimed to determine the prevalence and extent of late cardiac and cardiovascular sequelae after mild non-hospitalised SARS-CoV-2 infection.
Methods
Participants were recruited from COVIDsortium, a three-hospital prospective study of 731 healthcare workers who underwent first wave weekly symptom, PCR and serology assessment over 4 months, with seroconversion in 21.5% (n = 157). At 6 months post infection, 74 seropositive and 75 age-, sex-, ethnicity-matched seronegative controls were recruited for cardiovascular phenotyping (comprehensive phantom-calibrated Cardiovascular Magnetic Resonance and blood biomarkers). Analysis was blinded, using objective AI analytics where available.
Results
149 subjects (mean age 37 years, range 18-63, 58% female) were recruited. Seropositive infections had been mild with case definition/non-case definition/asymptomatic disease in 45(61%), 18(24%) and 11(15%) with one person hospitalised (for 2 days). Between seropositive and seronegative groups, there were no differences in cardiac structure (left ventricular volumes, mass; atrial area), function (ejection fraction, global longitudinal shortening, aortic distensibility), tissue characterisation (T1, T2, ECV mapping, late gadolinium enhancement) or biomarkers (troponin, NT-proBNP). With abnormal defined by the 75 seronegatives (2 standard deviations from mean, e.g. EF < 54%, septal T1 > 1072ms, septal T2 > 52.4ms), individuals had abnormalities including reduced EF (n = 2, minimum 50%), T1 elevation (n = 6), T2 elevation (n = 9), LGE (n = 13, median 1%, max 5% of myocardium), biomarker elevation (borderline troponin elevation in 4; all NT-proBNP normal). These were distributed equally between seropositive and seronegative individuals.
Conclusions
Cardiovascular abnormalities are no more common in seropositive vs seronegative otherwise healthy, workforce representative individuals 6 months post mild SARS-CoV-2 infection. Our study provides societal reassurance for the cardiovascular health of working-aged individuals with convalescence from mild SARS-CoV-2. Screening asymptomatic individuals following mild diseases is not indicated.
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Lau C, Kalantari B, Batts KP, Ferrell LD, Nyberg SL, Graham RP, Moreira RK. The Voronoi theory of the normal liver lobular architecture and its applicability in hepatic zonation. Sci Rep 2021; 11:9343. [PMID: 33927276 PMCID: PMC8085188 DOI: 10.1038/s41598-021-88699-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2020] [Accepted: 04/12/2021] [Indexed: 11/24/2022] Open
Abstract
The precise characterization of the lobular architecture of the liver has been subject of investigation since the earliest historical publications, but an accurate model to describe the hepatic lobular microanatomy is yet to be proposed. Our aim was to evaluate whether Voronoi diagrams can be used to describe the classic liver lobular architecture. We examined the histology of normal porcine and human livers and analyzed the geometric relationships of various microanatomic structures utilizing digital tools. The Voronoi diagram model described the organization of the hepatic classic lobules with overall accuracy nearly 90% based on known histologic landmarks. We have also designed a Voronoi-based algorithm of hepatic zonation, which also showed an overall zonal accuracy of nearly 90%. Therefore, we have presented evidence that Voronoi diagrams represent the basis of the two-dimensional organization of the normal liver and that this concept may have wide applicability in liver pathology and research.
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Timofte I, Wells C, Hersi K, Ryan A, Varghese A, Vesselinov R, Iacono A, Assadi J, Davis D, Li G, Herr D, Harrington T, Griffith B, Lau C, Krupnick A, Madathil R, Rabin J, Alon G, Parker E, Baer D, Magder L, Terrin M, Verceles A. Nutritional Supplementation and Neuromuscular Electrical Stimulation in Lung Transplant Patients. J Heart Lung Transplant 2021. [DOI: 10.1016/j.healun.2021.01.1012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Joy G, Crane JD, Lau C, Augusto J, Brown LAE, Chowdhary A, Kotecha T, Plein S, Fontana M, Moon JC, Kellman P, Xue H, Cruickshank JK, Mcgowan BM, Manisty C. Impact of obesity on myocardial microvasculature assessed using fully-automated inline myocardial perfusion mapping CMR. Eur Heart J Cardiovasc Imaging 2021. [DOI: 10.1093/ehjci/jeaa356.296] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Funding Acknowledgements
Type of funding sources: Public Institution(s). Main funding source(s): Guy"s and St Thomas" Charity University College London Hospitals Biomedical Research Centre
Background
Obesity and cardiovascular disease are associated, but the relationship is poorly understood. Myocardial perfusion, metabolic derangement and lipotoxicity appear adversely associated in many scenarios (myocardial injury, diastolic dysfunction, diabetes). Altered perfusion (by PET) predicts outcome, and it is hypothesised that perfusion derangement is part of causality for cardiac disease and adverse outcomes.
Purpose
To assess the presence and pattern of myocardial microvascular dysfunction in patients with obesity (scheduled for bariatric surgery) using stress quantitative perfusion mapping.
Methods
38 subjects with obesity planned to undergo bariatric surgery and 38 age and sex matched healthy volunteers (no diabetes, no hypertension) underwent anthropometry, biochemistry and CMR at 1.5T (Siemens) with cine imaging, stress (adenosine 140-210 mcg/kg/min) and rest fully-automated quantitative perfusion mapping.
Results
Bariatric patients had a higher BMI (44 ± 6.4 vs 26.5 ± 4kg/m2 p = 0.001); 58%(22) were diabetic and 58%(22) had hypertension. Bariatric patients had higher absolute but lower indexed end-diastolic volumes, and overall higher ejection fractions (+5%) (see Table). Rest myocardial blood flow (MBF) in bariatric patients was the same (1.00 ± 0.3 vs 0.88 ± 0.24 p = 0.052), but stress perfusion results were significantly lower both for stress MBF (2.35 ± 0.69 vs 2.93 ± 0.76ml/g/min p = 0.001) and myocardial perfusion reserve (MPR 2.48 ± 0.82 vs 3.4 ± 0.81ml/g/min p = 0.0001). Although this was transmural, the endocardial stress MBF was particularly negatively affected in the bariatric cohort compared to controls (endocardial MBF 2.16 ± 0.65 vs 2.82 ± 0.73ml/g/min, p = 0.0001 vs epicardial MBF: 2.52 ± 0.76 vs 3.06 ± 0.79 p = 0.003), meaning there was an increased endo-epicardial stress MBF gradient in bariatric patients (0.87 ± 0.12 vs 0.92 ± 0.07 p = 0.03).
Conclusion
Compared to healthy controls, patients with obesity have abnormal myocardial stress perfusion with reduced global perfusion, perfusion reserve and an increased transmyocardial perfusion gradient.
Table - myocardial perfusion parameters Category Bariatric patients n = 38 Controls n = 38 p value Age (years) 48 ± 11 45 ± 13 0.25 n male (%) 12 (32%) 10 (36%) 0.32 LVEDV (ml) 168 ± 37 149 ± 31 0.017 LVEDVi (ml/m2) 70.4 ± 12.3 78.8 ± 12.1 0.004 LV Mass (g) 116 ± 31 99 ± 28 0.019 EF (%) 70 ± 8 65 ± 5 0.002 LVEDV - left ventricular end-diastolic volume, EF - ejection fraction
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Lim A, N.A.Rahim, Periyasamy P, Mat W, Lau C. Mortality and microbiological clearance among critically ill patients receiving Polymyxin B in a Malaysian ICU: A 10 years retrospective study. Int J Infect Dis 2020. [DOI: 10.1016/j.ijid.2020.09.724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Bicho Augusto J, Johner N, Shah D, Nordin S, Knott K, Lau C, Alfarih M, Seraphim A, Vijapurapu R, Ramaswami U, Steeds R, Kozor R, Hughes D, Moon J, Namdar M. The myocardial phenotype of Fabry disease pre-hypertrophy and pre-detectable storage. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.2132] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background
Cardiac involvement in Fabry Disease (FD) occurs prior to left ventricular hypertrophy (LVH) and is characterized by low myocardial native T1 with storage reflected by cardiovascular magnetic resonance (CMR) and ECG changes.
Objectives
We hypothesize that a pre-storage myocardial phenotype might occur even earlier, prior to T1 lowering.
Methods
FD patients and age, sex and heart rate matched healthy controls underwent same-day ECG with advanced analysis and multiparametric CMR (cines, global longitudinal strain [GLS], T1 and T2 mapping, stress perfusion [myocardial blood flow, MBF] and late gadolinium enhancement [LGE]).
Results
114 Fabry patients (46±13 years, 61% female) and 76 controls (49±15 years, 50% female) were included. In pre-LVH FD (n=72, 63%), a low T1 (n=32/72, 44%) was associated with a constellation of ECG and functional abnormalities compared to normal T1 FD patients and controls. However, pre-LVH FD with normal T1 (n=40/72, 56%) also had abnormalities compared to controls: reduced GLS (−18±2 vs −20±2%, P<0.001), microvascular changes (lower MBF 2.5±0.7 vs 3.0±0.8mL/g/min, P=0.028), subtle T2 elevation (50±4 vs 48±2ms, p=0.027) and limited LGE (%LGE 0.3±1.1 vs 0%, P=0.004). ECG abnormalities included shorter P wave duration (88±12 vs 94±15ms, P=0.010) and T wave peak time (Tonset–Tpeak; 104±28 vs 115±20ms, P=0.015), resulting in a more symmetric T wave with lower T wave time ratio (Tonset–Tpeak)/(Tpeak–Tend) (1.5±0.4 vs 1.8±0.4, P<0.001) compared to controls.
Conclusions
FD has a measurable myocardial phenotype pre-LVH and pre-detectable myocyte storage with microvascular dysfunction, subtly impaired GLS and altered atrial depolarization and ventricular repolarization intervals.
Proposed stages of cardiac involvement
Funding Acknowledgement
Type of funding source: None
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Lau C, Turcich MR, Smith EO. Early detection of parenting stress in mothers of preterm infants during their first-year home. BMC Psychol 2020; 8:66. [PMID: 32576260 PMCID: PMC7313173 DOI: 10.1186/s40359-020-00435-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 06/17/2020] [Indexed: 11/11/2022] Open
Abstract
Background Maternal stress following the birth of an infant is well acknowledged. It is particularly so when infants are born prematurely as their mothers cannot fully take on their parenting role until their infant(s) is discharged from neonatal intensive care units (NICUs). In this exploratory study, we examined whether these mothers’ parenting stress would lessen during their first-year reunification with their infant(s) as they settle into motherhood at home. Methods Two groups of mothers with infants born between 24- and 33-week gestational age were recruited. A group of 25 mothers were monitored at their infants’ 1-month corrected age (CA) and a second group of 24 mothers were monitored at their infants’ 12-month CA. Subjects completed the long form Parental Stress Index (PSI) ranking how stressful they perceive the individual subscales in the Child and Parent Domains of the self-reported questionnaire (PSI-3; Abidin; PAR Inc). The PSI theorizes that the stress mothers perceive is a resultant of their respective characteristics, interactions with their infant(s), family, and environment. Statistical analyses include descriptive statistics, χ2 square analysis, and independent t-test. Results There was no significant difference in the levels of perceived stress in the PSI subscales between the two groups of mothers at 1- and 12-month CA. Scores for the majority of respondents fell within the 15th to 80th percentile (% ile) distribution of Abidin’s normative population, with some mothers falling below the 15th % ile. Discussion/conclusion The data collected suggest that: 1. the perceived stress experienced by mothers during their first-year reunited with their preterm infants is within the normal range observed in Abidin’s normative population. 2. As the PSI is a self-reported survey, care providers need to be aware that some mothers may downplay their stress responses. 3. With the ability to monitor individual participants, the PSI can be readily offered to mothers at their infants’ first year routine clinical visits to assist in the early identification of parenting issues that may threaten the development of a healthy mother-infant dyad. Early appropriate guidance and social support would help “at-risk” mothers develop more constructive parenting routines.
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Farry T, Lau C, Keates H, McEwen M, Woldeyohannes S, Barnes T, Perkins N, Goodwin W. Comparison of two formulations of alfaxalone in laboratory zebra fish (Danio rerio) for use in immersion anaesthesia. Vet Anaesth Analg 2019. [DOI: 10.1016/j.vaa.2019.08.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Caneses JF, Piotrowicz PA, Biewer TM, Goulding RH, Lau C, Showers M, Rapp J. Ion Fluxes and Neutral Gas Ionization Efficiency of the 100-kW Light-Ion Helicon Plasma Source Concept for the Material Plasma Exposure eXperiment. FUSION SCIENCE AND TECHNOLOGY 2019. [DOI: 10.1080/15361055.2019.1622988] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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25
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Bhuva A, Bai W, Lau C, Davies R, Yang Y, Bulluck H, Mcalindon E, Cole GD, Petersen SE, Greenwood JP, Bucciarelli-Ducci C, Hughes AD, Rueckert D, Moon JC, Manisty CH. 349Fully automated left ventricular analysis matches clinician precision: a multi-centre, multi-vendor, multi-field strength, multi-disease scan:rescan CMR study. Eur Heart J Cardiovasc Imaging 2019. [DOI: 10.1093/ehjci/jez103.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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