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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. Rev Sci Instrum 2023; 94:073504. [PMID: 37493501 DOI: 10.1063/5.0149654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- S Chowdhury
- Physics and Astronomy Department, University of California Los Angeles, Los Angeles, California 90098, USA
| | - N A Crocker
- Physics and Astronomy Department, University of California Los Angeles, Los Angeles, California 90098, USA
| | - W A Peebles
- Physics and Astronomy Department, University of California Los Angeles, Los Angeles, California 90098, USA
| | - T L Rhodes
- Physics and Astronomy Department, University of California Los Angeles, Los Angeles, California 90098, USA
| | - L Zeng
- Physics and Astronomy Department, University of California Los Angeles, Los Angeles, California 90098, USA
| | - R Lantsov
- Physics and Astronomy Department, University of California Los Angeles, Los Angeles, California 90098, USA
| | - B Van Compernolle
- General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA
| | - M Brookman
- General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA
| | - R I Pinsker
- General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA
| | - C Lau
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
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2
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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. Rev Sci Instrum 2023; 94:063506. [PMID: 37862546 DOI: 10.1063/5.0132246] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- E Leppink
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - C Lau
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - Y Lin
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
| | - S J Wukitch
- MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139, USA
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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] [What about the content of this article? (0)] [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] [What about the content of this article? (0)] [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] [What about the content of this article? (0)] [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] [What about the content of this article? (0)] [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] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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8
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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] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Abstract
Background: Maternal stress in neonatal intensive care units (NICUs) is well acknowledged. However, there is currently no well-defined support at how to best assist mothers during their infants’ hospitalization. Not only must they confront at the same time their infant’s fragility, but also their own personal trials. In this exploratory study, we examined whether the Multiple-Stressor mediational modeling approach commonly used in Ecology could be used to better assist these parents. This approach calls attention to the overall impact that multiple stressors can have on an organism, i.e., not only in regard to their individual effects, but just as importantly, through their interactions with each other, be they positive or negative. It is hypothesized that the use of such mediational modeling could improve our understanding of the overall impact that multiple stressors can have on NICU mothers. Methods: At 2 weeks postpartum, 30 mothers with infants born between 24 and 29 weeks gestation responded to the following self-reported psychological outcome measures: Affect Intensity Measure (AIM); Crowne-Marlowe Social Desirability Scale (CM); Edinburgh Postnatal Depression Scale (EDPS); Brief Symptom Inventory-Anxiety (BSI-Anx); Parental Stress Scale: NICU (PSS:NICU); Multidimensional Scale of Perceived Social Support (MSPSS); and Coping Inventory for Stressful Situations (CISS). The “Best Subsets Regression” analysis (www.minitab.com) was used to identify the four interactive maternal outcome measures that best correlated with the mediational stress models of interest, namely, Depression, Anxiety, parental NICU stress, Perceived Social Support, and Coping skills. Results: The following mediational models of maternal stress outcomes during their infant’s NICU hospitalization were identified: depression, anxiety, stress of the sights and sounds in the NICU, “the looks of my baby”, my “inability” to be a parent, perceived social support, and coping skills. Conclusions: It is advanced that the use of the Multiple-Stressor approach, with its ability to identify factors associated with particular stressors, can offer psychosocial providers a more tangible understanding of the maternal key elements at the source of maternal stress in NICUs. It is expected that to ease the stressful experiences these mothers encounter, such approach will facilitate the development of more effective interventions to assist these parents’ challenges than currently available.
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Affiliation(s)
- Chantal Lau
- Baylor College of Medicine, Department of Pediatrics, Houston, TX, USA
| | - Marie R Turcich
- Baylor College of Medicine, Department of Pediatrics, Houston, TX, USA
| | - J Kennard Fraley
- Baylor College of Medicine, Department of Pediatrics, Houston, TX, USA
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- C Lau
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - A Shabbir
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - K S Rathod
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - I Chhetri
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - M Ono
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - A J P Hamers
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - J J Amarin
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - A Ibrahim
- University of Southampton, Southampton, United Kingdom
| | - G Nuredini
- Barts Health NHS Trust, London, United Kingdom
| | - T Godec
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - V Kapil
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - A Ahluwalia
- William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
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11
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- A Shabbir
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - C Lau
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - K S Rathod
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - I Chhetri
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - A Haque
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - T Godec
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - R S Khambata
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - V Kapil
- St Bartholomews and Queen Mary University, London, United Kingdom
| | - A Ahluwalia
- St Bartholomews and Queen Mary University, London, United Kingdom
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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] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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13
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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] [What about the content of this article? (0)] [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] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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15
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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] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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16
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- G Joy
- Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - J Artico
- Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - H Kurdi
- Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - C Lau
- Queen Mary University of London, London, United Kingdom of Great Britain & Northern Ireland
| | - RD Adam
- Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - KM Menacho
- Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - I Pierce
- Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - G Captur
- Royal Free Hospital, London, United Kingdom of Great Britain & Northern Ireland
| | - R Davies
- University College of London, London, United Kingdom of Great Britain & Northern Ireland
| | - EB Schelbert
- University of Pittsburgh, Pittsburgh, United States of America
| | - M Fontana
- Royal Free Hospital, London, United Kingdom of Great Britain & Northern Ireland
| | - P Kellman
- National Institutes of Health, Bethesda, United States of America
| | - TA Treibel
- Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - C Manisty
- Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - JC Moon
- Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- C Lau
- Department of Computer Science, Rutgers University, Brunswick, NJ, USA
| | - B Kalantari
- Department of Computer Science, Rutgers University, Brunswick, NJ, USA
| | | | - L D Ferrell
- Department of Pathology, University of California, San Francisco, CA, USA
| | - S L Nyberg
- Division of Transplantation Surgery, Department of Surgery, Mayo Clinic, Rochester, MN, USA
| | - R P Graham
- Department of Pathology and Laboratory Medicine, Mayo Clinic, Rochester, MN, USA
| | - Roger K Moreira
- Department of Pathology and Laboratory Medicine, Mayo Clinic, Rochester, MN, USA.
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18
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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] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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19
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- G Joy
- Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - JD Crane
- King"s College London, Department of Diabetes and Nutritional Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - C Lau
- Queen Mary University of London, London, United Kingdom of Great Britain & Northern Ireland
| | - J Augusto
- University College London, Institute of Cardiovascular Science, London, United Kingdom of Great Britain & Northern Ireland
| | - LAE Brown
- University of Leeds, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds, United Kingdom of Great Britain & Northern Ireland
| | - A Chowdhary
- University of Leeds, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds, United Kingdom of Great Britain & Northern Ireland
| | - T Kotecha
- Royal Free Hospital, London, United Kingdom of Great Britain & Northern Ireland
| | - S Plein
- University of Leeds, Leeds Institute of Cardiovascular and Metabolic Medicine, Leeds, United Kingdom of Great Britain & Northern Ireland
| | - M Fontana
- University College London, Institute of Cardiovascular Science, London, United Kingdom of Great Britain & Northern Ireland
| | - JC Moon
- University College London, Institute of Cardiovascular Science, London, United Kingdom of Great Britain & Northern Ireland
| | - P Kellman
- National Institutes of Health, National Heart, Lung, and Blood Institute, Bethesda, United States of America
| | - H Xue
- National Institutes of Health, National Heart, Lung, and Blood Institute, Bethesda, United States of America
| | - JK Cruickshank
- King"s College London, Department of Diabetes and Nutritional Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - BM Mcgowan
- King"s College London, Department of Diabetes and Nutritional Sciences, London, United Kingdom of Great Britain & Northern Ireland
| | - C Manisty
- University College London, Institute of Cardiovascular Science, London, United Kingdom of Great Britain & Northern Ireland
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20
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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] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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21
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
| | - N Johner
- Geneva University Hospitals, Cardiology Division, Geneva, Switzerland
| | - D Shah
- Geneva University Hospitals, Cardiology Division, Geneva, Switzerland
| | - S Nordin
- Barts Health NHS Trust, London, United Kingdom
| | - K Knott
- University College London, London, United Kingdom
| | - C Lau
- Barts Health NHS Trust, London, United Kingdom
| | - M Alfarih
- University College London, London, United Kingdom
| | - A Seraphim
- University College London, London, United Kingdom
| | - R Vijapurapu
- Queen Elizabeth Hospital Birmingham, Department of Cardiology, Birmingham, United Kingdom
| | - U Ramaswami
- Royal Free Hospital, lysosomal storage disorders unit, London, United Kingdom
| | - R Steeds
- Queen Elizabeth Hospital Birmingham, Department of Cardiology, Birmingham, United Kingdom
| | - R Kozor
- University of Sydney, Sydney Medical School, Sydney, Australia
| | - D Hughes
- Royal Free Hospital, lysosomal storage disorders unit, London, United Kingdom
| | - J Moon
- Barts Health NHS Trust, London, United Kingdom
| | - M Namdar
- Geneva University Hospitals, Cardiology Division, Geneva, Switzerland
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22
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Affiliation(s)
- C Lau
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA.
| | - M R Turcich
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
| | - E O Smith
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, 77030, USA
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23
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Abstract
The increase in preterm infants' survival over the last 30 years has shed light over their inability to feed by mouth safely and efficiently. With adverse events such as increased risks for oxygen desaturation, bradycardia, penetration/aspiration, infants' hospitalization in neonatal intensive care units (NICUs) are understandably prolonged. Unfortunately, this leads to delayed mother-infant reunion, maternal stress, breastfeeding obstacles, and increased medical costs. Such impediments have stimulated clinicians and researchers to better understand the underlying causes and develop evidence-based solutions to assist these infants. However, it is notable that the research-to-practice translation of this knowledge has been limited as there are still no validated guidelines or protocols as how to best diagnose and care for these infants. This report revisits the immature physiologic functions at the root of these infants' oral feeding difficulties, the current practices, and the recent availability of evidence-based efficacious tools and interventions. Taking advantage of the latter, it presents a renewed perspective of how management strategies can be tailored to the specific needs of individual patients.
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Affiliation(s)
- Chantal Lau
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, United States
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24
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Lyu T, Zhang Y, Hu X, Gu Y, Li L, Lau C. Management of Oral Feeding Challenges in Neonatal Intensive Care Units (NICUs): A National Survey in China. Front Pediatr 2020; 8:336. [PMID: 32671001 PMCID: PMC7328344 DOI: 10.3389/fped.2020.00336] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2020] [Accepted: 05/21/2020] [Indexed: 12/19/2022] Open
Abstract
Objectives: To investigate the current practices of oral feeding difficulties facing high-risk infants in Chinese NICUs. Methods: A questionnaire to survey infant oral feeding practices was distributed to 100 level II and III Chinese neonatal intensive care units (NICUs). Results: Responses were obtained from 88 NICUs. No Units had any structured guidelines regarding the management of infant oral feeding as they transitioned from tube to independent oral feeding. In 54 (61.4%) NICUs, nurses and physicians made shared decisions on when oral feeding were to be initiated. Fifty-four (61.4%) and 22 (25.0%) NICUs used postmenstrual age (PMA) or weight at PMA as a criterion for initiating oral feedings, respectively. The top three criteria to determine introduction of oral feeding were severity of disease, presence of sucking reflex, and trial feeding success. Adverse events were used by 78 Units as indices of oral feeding difficulty. Twenty (22.7%) and 25 (28.4%) Units had access to occupational therapists or nurses who provided oral motor interventions during feeding, i.e., oral support (chin and cheek support, aid to deglutition), non-nutritive sucking with pacifier, and oral stimulation. Conclusions: The management of oral feeding issues in NICUs vary widely in China in relation to the assessment of readiness to oral feeding, daily oral feeding practices and interventions used by staff. It is proposed that an educational program focused on the physiology of infant oral feeding, available evidence-based tools and interventions would assist NICU caregivers develop structured guidelines to improve infants' safe and efficient attainment of independent oral feeding.
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Affiliation(s)
- Tianchan Lyu
- Neonatal Intensive Care Unit, Children's Hospital of Fudan University, Shanghai, China
| | - Yuxia Zhang
- Nursing Department, Children's Hospital of Fudan University, Shanghai, China
| | - Xiaojing Hu
- Nursing Department, Zhongshan Hospital of Fudan University, Shanghai, China
| | - Ying Gu
- Nursing Department, Zhongshan Hospital of Fudan University, Shanghai, China
| | - Liling Li
- Neonatal Intensive Care Unit, Children's Hospital of Fudan University, Shanghai, China
| | - Chantal Lau
- Department of Pediatrics, Baylor College of Medicine, Houston, TX, United States
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25
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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] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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26
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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] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Affiliation(s)
- J. F. Caneses
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
| | - P. A. Piotrowicz
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
- University of Illinois at Urbana-Champaign, Department of Nuclear, Plasma and Radiological Engineering, Center for Plasma-Material Interactions, Urbana, Illinois 61801
| | - T. M. Biewer
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
| | - R. H. Goulding
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
| | - C. Lau
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
| | - M. Showers
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
- University of Tennessee, Knoxville, Tennessee 37996
| | - J. Rapp
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831
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27
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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] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- A Bhuva
- University College London, Institute of Cardiovasular Science, London, United Kingdom of Great Britain & Northern Ireland
| | - W Bai
- Imperial College London, London, United Kingdom of Great Britain & Northern Ireland
| | - C Lau
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - R Davies
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - Y Yang
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - H Bulluck
- University College London, Institute of Cardiovasular Science, London, United Kingdom of Great Britain & Northern Ireland
| | - E Mcalindon
- Bristol Heart Institute, Bristol, United Kingdom of Great Britain & Northern Ireland
| | - G D Cole
- Imperial College London, London, United Kingdom of Great Britain & Northern Ireland
| | - S E Petersen
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - J P Greenwood
- University of Leeds, Leeds, United Kingdom of Great Britain & Northern Ireland
| | - C Bucciarelli-Ducci
- Bristol Heart Institute, Bristol, United Kingdom of Great Britain & Northern Ireland
| | - A D Hughes
- University College London, Institute of Cardiovasular Science, London, United Kingdom of Great Britain & Northern Ireland
| | - D Rueckert
- Imperial College London, London, United Kingdom of Great Britain & Northern Ireland
| | - J C Moon
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
| | - C H Manisty
- Barts Health NHS Trust, Barts Heart Centre, London, United Kingdom of Great Britain & Northern Ireland
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28
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Illes J, McCall IC, Lau C, Minielly N. Ethical considerations for brain recording and stimulating neurotechnologies available in the open marketplace. Brain Stimul 2019. [DOI: 10.1016/j.brs.2018.12.964] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
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29
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Donald PM, Illes J, Lau C, McCall IC. Regulatory oversight for DBS: Current framework for device recall in North America. Brain Stimul 2019. [DOI: 10.1016/j.brs.2018.12.966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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30
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Landsem A, Fure H, Krey Ludviksen J, Christiansen D, Lau C, Mathisen M, Bergseth G, Nymo S, Lappegård KT, Woodruff TM, Espevik T, Mollnes TE, Brekke OL. Complement component 5 does not interfere with physiological hemostasis but is essential for Escherichia coli-induced coagulation accompanied by Toll-like receptor 4. Clin Exp Immunol 2018; 196:97-110. [PMID: 30444525 PMCID: PMC6422650 DOI: 10.1111/cei.13240] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/09/2018] [Indexed: 12/18/2022] Open
Abstract
There is a close cross-talk between complement, Toll-like receptors (TLRs) and coagulation. The role of the central complement component 5 (C5) in physiological and pathophysiological hemostasis has not, however, been fully elucidated. This study examined the effects of C5 in normal hemostasis and in Escherichia coli-induced coagulation and tissue factor (TF) up-regulation. Fresh whole blood obtained from six healthy donors and one C5-deficient individual (C5D) was anti-coagulated with the thrombin inhibitor lepirudin. Blood was incubated with or without E. coli in the presence of the C5 inhibitor eculizumab, a blocking anti-CD14 monoclonal antibody (anti-CD14) or the TLR-4 inhibitor eritoran. C5D blood was reconstituted with purified human C5. TF mRNA was measured by quantitative polymerase chain reaction (qPCR) and monocyte TF and CD11b surface expression by flow cytometry. Prothrombin fragment 1+2 (PTF1·2) in plasma and microparticles exposing TF (TF-MP) was measured by enzyme-linked immunosorbent assay (ELISA). Coagulation kinetics were analyzed by rotational thromboelastometry and platelet function by PFA-200. Normal blood with eculizumab as well as C5D blood with or without reconstitution with C5 displayed completely normal biochemical hemostatic patterns. In contrast, E. coli-induced TF mRNA and TF-MP were significantly reduced by C5 inhibition. C5 inhibition combined with anti-CD14 or eritoran completely inhibited the E. coli-induced monocyte TF, TF-MP and plasma PTF1·2. Addition of C5a alone did not induce TF expression on monocytes. In conclusion, C5 showed no impact on physiological hemostasis, but substantially contributed to E. coli-induced procoagulant events, which were abolished by the combined inhibition of C5 and CD14 or TLR-4.
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Affiliation(s)
- A Landsem
- Research Laboratory and Department of Laboratory Medicine, Nordland Hospital Trust, Bodø, Norway.,Department of Clinical Medicine, UiT - The Arctic University of Norway, Tromsø, Norway
| | - H Fure
- Research Laboratory and Department of Laboratory Medicine, Nordland Hospital Trust, Bodø, Norway
| | - J Krey Ludviksen
- Research Laboratory and Department of Laboratory Medicine, Nordland Hospital Trust, Bodø, Norway
| | - D Christiansen
- Research Laboratory and Department of Laboratory Medicine, Nordland Hospital Trust, Bodø, Norway
| | - C Lau
- Research Laboratory and Department of Laboratory Medicine, Nordland Hospital Trust, Bodø, Norway
| | - M Mathisen
- Research Laboratory and Department of Laboratory Medicine, Nordland Hospital Trust, Bodø, Norway
| | - G Bergseth
- Research Laboratory and Department of Laboratory Medicine, Nordland Hospital Trust, Bodø, Norway
| | - S Nymo
- Research Laboratory and Department of Laboratory Medicine, Nordland Hospital Trust, Bodø, Norway.,Division of Medicine, Nordland Hospital Trust, Bodø, Norway
| | - K T Lappegård
- Department of Clinical Medicine, UiT - The Arctic University of Norway, Tromsø, Norway.,Division of Medicine, Nordland Hospital Trust, Bodø, Norway
| | - T M Woodruff
- School of Biomedical Sciences, Faculty of Medicine, The University of Queensland, Brisbane, Australia
| | - T Espevik
- Centre of Molecular Inflammation Research, and Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - T E Mollnes
- Research Laboratory and Department of Laboratory Medicine, Nordland Hospital Trust, Bodø, Norway.,Department of Clinical Medicine, UiT - The Arctic University of Norway, Tromsø, Norway.,K. G. Jebsen TREC, UiT - The Arctic University of Norway, Tromsø, Norway.,Department of Immunology, Oslo University Hospital Rikshospitalet and University of Oslo, Norway.,Centre of Molecular Inflammation Research, and Department of Cancer Research and Molecular Medicine, Norwegian University of Science and Technology, Trondheim, Norway
| | - O-L Brekke
- Research Laboratory and Department of Laboratory Medicine, Nordland Hospital Trust, Bodø, Norway.,Department of Clinical Medicine, UiT - The Arctic University of Norway, Tromsø, Norway
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31
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Gupta R, Chevalier D, Saluja J, Lau C, Wang C, Fakih M. ctDNA assays identify alterations in RAS, EGFR, and cMET that are unique to RAS-WT patients progressing on anti-EGFR therapy. Ann Oncol 2018. [DOI: 10.1093/annonc/mdy281.090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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32
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Amanam I, Chao J, Lim D, Rahmanuddin S, Schrock A, Ali S, Lau C, Chevalier D, Harris E, Saluja J, Wang C, Fakih M. Lower tumor mutational burden (TMB) and hepatic metastases may predict for lack of response to PD-1 blockade in MSI-H metastatic colorectal cancer (MCRC). Ann Oncol 2018. [DOI: 10.1093/annonc/mdy281.081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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33
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Martin EH, Lau C, Brookman MW, Lohr J. A spectroscopic electric field vector imaging diagnostic for electron cyclotron heating systems. Rev Sci Instrum 2018; 89:10D117. [PMID: 30399893 DOI: 10.1063/1.5038670] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Accepted: 06/11/2018] [Indexed: 06/08/2023]
Abstract
An experimental measurement of the wave electric field vector provides important data that can be used to directly compare against 3D full-wave simulations. This direct comparison yields the fastest approach toward identifying missing physics in computational models and providing a high fidelity validation platform. In this paper, we present a diagnostic that is capable of imaging the Electron Cyclotron (EC) wave electric field vector by acquiring filtered images of polarized D β spectral satellites. The diagnostic is designed to have a spatial and temporal resolution on the order of 100 μm and 100 μs, respectively. The diagnostic purpose is to provide experimental data for the direct validation of full-wave codes used to predict EC beam propagation and absorption and to provide real-time monitoring of EC waves.
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Affiliation(s)
- E H Martin
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
| | - C Lau
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37830, USA
| | - M W Brookman
- General Atomics, 3550 General Atomics Ct., San Diego, California 92121, USA
| | - J Lohr
- General Atomics, 3550 General Atomics Ct., San Diego, California 92121, USA
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Schmitz L, Deng B, Thompson M, Gota H, Lau C, Fulton DP, Lin Z, Tajima T, Binderbauer M. Combination Doppler backscattering/cross-polarization scattering diagnostic for the C-2W field-reversed configuration. Rev Sci Instrum 2018; 89:10H116. [PMID: 30399746 DOI: 10.1063/1.5038914] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 06/20/2018] [Indexed: 06/08/2023]
Abstract
A versatile combination Doppler backscattering and Cross-Polarization Scattering (CPS) diagnostic for the C-2W beam-driven field-reversed configuration is described. This system is capable of measuring density fluctuations and perpendicular magnetic field fluctuations across a wide wavenumber range (2.5 ≤ k θ ρ s ≤ 50), with typical resolution Δk θ/k θ ≤ 0.4-0.8. Four tunable frequencies (26 GHz ≤ f ≤ 60 GHz corresponding to plasma cut-off densities 0.8 × 1019 ≤ n e ≤ 4.4 × 1019 m-3) are launched via quasi-optical beam combiners/polarizers and an adjustable parabolic focusing mirror selecting the beam incidence angle. GENRAY ray tracing shows that the incident O-mode and backscattered CPS X-mode beam trajectories for C-2W plasma parameters nearly overlap, allowing simultaneous detection of ñ and B̃ r or B̃ θ from essentially the same scattering volume.
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Affiliation(s)
- L Schmitz
- Department of Physics and Astronomy, University of California Los Angeles, Los Angeles, California 90095, USA
| | - B Deng
- TAE Technologies, Inc., Foothill Ranch, California 92610, USA
| | - M Thompson
- TAE Technologies, Inc., Foothill Ranch, California 92610, USA
| | - H Gota
- TAE Technologies, Inc., Foothill Ranch, California 92610, USA
| | - C Lau
- TAE Technologies, Inc., Foothill Ranch, California 92610, USA
| | - D P Fulton
- TAE Technologies, Inc., Foothill Ranch, California 92610, USA
| | - Z Lin
- Department of Physics and Astronomy, University of California Irvine, Irvine, California 92697, USA
| | - T Tajima
- TAE Technologies, Inc., Foothill Ranch, California 92610, USA
| | - M Binderbauer
- TAE Technologies, Inc., Foothill Ranch, California 92610, USA
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Lau C. Effect of short-term high-intensity noise exposure on auditory physiology: a functional magnetic resonance imaging study. Hong Kong Med J 2018; 24 Suppl 4:46-47. [PMID: 30135276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023] Open
Affiliation(s)
- C Lau
- Department of Physics, City University of Hong Kong
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Spong DA, Heidbrink WW, Paz-Soldan C, Du XD, Thome KE, Van Zeeland MA, Collins C, Lvovskiy A, Moyer RA, Austin ME, Brennan DP, Liu C, Jaeger EF, Lau C. First Direct Observation of Runaway-Electron-Driven Whistler Waves in Tokamaks. Phys Rev Lett 2018; 120:155002. [PMID: 29756886 DOI: 10.1103/physrevlett.120.155002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Indexed: 06/08/2023]
Abstract
DIII-D experiments at low density (n_{e}∼10^{19} m^{-3}) have directly measured whistler waves in the 100-200 MHz range excited by multi-MeV runaway electrons. Whistler activity is correlated with runaway intensity (hard x-ray emission level), occurs in novel discrete frequency bands, and exhibits nonlinear limit-cycle-like behavior. The measured frequencies scale with the magnetic field strength and electron density as expected from the whistler dispersion relation. The modes are stabilized with increasing magnetic field, which is consistent with wave-particle resonance mechanisms. The mode amplitudes show intermittent time variations correlated with changes in the electron cyclotron emission that follow predator-prey cycles. These can be interpreted as wave-induced pitch angle scattering of moderate energy runaways. The tokamak runaway-whistler mechanisms have parallels to whistler phenomena in ionospheric plasmas. The observations also open new directions for the modeling and active control of runaway electrons in tokamaks.
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Affiliation(s)
- D A Spong
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - W W Heidbrink
- University of California-Irvine, Irvine, California 92697, USA
| | - C Paz-Soldan
- General Atomics, San Diego, California 92186-5608, USA
| | - X D Du
- University of California-Irvine, Irvine, California 92697, USA
| | - K E Thome
- Oak Ridge Associated Universities, P.O. Box 117, Oak Ridge, Tennessee 37831, USA
| | | | - C Collins
- General Atomics, San Diego, California 92186-5608, USA
| | - A Lvovskiy
- Oak Ridge Associated Universities, P.O. Box 117, Oak Ridge, Tennessee 37831, USA
| | - R A Moyer
- University of California-San Diego, La Jolla, California 92093, USA
| | - M E Austin
- University of Texas, Austin, Texas 78705, USA
| | - D P Brennan
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - C Liu
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA
| | - E F Jaeger
- XCEL Engineering, Oak Ridge, Tennessee 37830, USA
| | - C Lau
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
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Shurrab M, Kaoutskaia A, Baranchuk A, Lau C, Singarajah T, Lashevsky I, Newman D, Healey JS, Crystal E. Are there increased periprocedural complications with the MRI-conditional Medtronic Revo SureScan Pacing System? : A meta-analysis. Neth Heart J 2018; 26:233-239. [PMID: 29411288 PMCID: PMC5910305 DOI: 10.1007/s12471-018-1086-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND The use of magnetic resonance imaging (MRI)-conditional permanent pacemakers has increased significantly. In this meta-analysis, we examine the safety of MRI-conditional pacing systems in comparison with conventional systems. METHODS An electronic search was performed using major databases, including studies that compared the outcomes of interest between patients receiving MRI-conditional pacemakers (MRI group) versus conventional pacemakers (control group). RESULTS Six studies (5 retrospective and 1 prospective non-randomised) involving 2,118 adult patients were identified. The MRI-conditional pacemakers, deployed in 969 patients, were all from a single manufacturer (Medtronic Pacing System with 5086 leads). The rate of pacemaker lead dislodgement (atrial and ventricular) was significantly higher in the MRI group (3% vs. 1%, OR 2.47 (95% CI 1.26; 4.83), p = 0.008). The MRI group had a significantly higher rate of pericardial complications (2% vs. 1%, OR 4.23 (95% CI 1.18; 15.10), p = 0.03) and a numerically higher overall complication rate in comparison with the conventional group (6% vs. 3%, OR 2.02 (95% CI 0.88; 4.66), p = 0.10) but this was not statistically significant. CONCLUSIONS In this meta-analysis, the rates of pacemaker lead dislodgement and pericardial complications were significantly higher with the Medtronic MRI-conditional pacing system.
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Affiliation(s)
- M Shurrab
- Arrhythmia Services, Schulich Heart Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada. .,Division of Cardiology, Women's College Hospital, University of Toronto, Toronto, Ontario, Canada. .,Institute of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada.
| | - A Kaoutskaia
- Arrhythmia Services, Schulich Heart Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - A Baranchuk
- Division of Cardiology, Kingston General Hospital, Queen's University, Kingston, Ontario, Canada
| | - C Lau
- Arrhythmia Services, Schulich Heart Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - T Singarajah
- Arrhythmia Services, Schulich Heart Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - I Lashevsky
- Arrhythmia Services, Schulich Heart Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - D Newman
- Arrhythmia Services, Schulich Heart Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada
| | - J S Healey
- Population Health Research Institute, McMaster University, Hamilton, Ontario, Canada
| | - E Crystal
- Arrhythmia Services, Schulich Heart Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario, Canada.,Division of Cardiology, Women's College Hospital, University of Toronto, Toronto, Ontario, Canada
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Abstract
Breastfeeding is an experience that only a mother and her infant(s) can share. Infants who can feed from the breast receive not only the best nutrition but also, due to the close physical contact between mother and child, it is the optimal nurturance they can receive from their mother. When breastfeeding is trouble free, maternal well-being is uniquely heightened. However, breastfeeding remains a challenge for many mother-infant dyads and more so for those whose infants are born prematurely. This article introduces a conceptual model of the breastfeeding challenges facing preterm mother-infant dyads. It distinguishes between a maternal caregiving and an infant growth/development components. Within the maternal component, two primary elements are considered, that is, maternal behavioral and nutritional care. The two primary elements within the infant component include infant non-nutritional and nutritional growth/development. It is proposed that an improved understanding of the factors associated with these four elements and how they interplay with each other within individual dyads will facilitate the identification of the breastfeeding challenges facing these mother-infant entities. Due to the intimate relationships existing between a mother and her infant(s), it is further advanced that breastfeeding studies would be optimized if mother-infant pairs are studied as one entity rather than mother and infant separately. It is proposed that this conceptual model will assist health professionals develop personalized breastfeeding management plans for individual preterm mother-infant dyads, while furthering the development of evidence-based interventions to optimize their breastfeeding experiences.
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Affiliation(s)
- Chantal Lau
- Department of Pediatrics/Neonatology, Baylor College of Medicine , Houston, Texas
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Wang G, Peebles WA, Doyle EJ, Crocker NA, Wannberg C, Lau C, Hanson GR, Doane JL. Evaluation of low-frequency operational limit of proposed ITER low-field-side reflectometer waveguide run including miter bends. Rev Sci Instrum 2017; 88:103508. [PMID: 29092526 DOI: 10.1063/1.4995662] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The present design concept for the ITER low-field-side reflectometer transmission line (TL) consists of an ∼40 m long, 6.35 cm diameter helically corrugated waveguide (WG) together with ten 90° miter bends. This paper presents an evaluation of the TL performance at low frequencies (33-50 GHz) where the predicted HE11 mode ohmic and mode conversion losses start to increase significantly. Quasi-optical techniques were used to form a near Gaussian beam to efficiently couple radiation in this frequency range into the WG. It was observed that the output beams from the guide remained linearly polarized with cross-polarization power levels of ∼1.5%-3%. The polarization rotation due to the helical corrugations was in the range ∼1°-3°. The radiated beam power profiles typically show excellent Gaussian propagation characteristics at distances >20 cm from the final exit aperture. The round trip propagation loss was found to be ∼2.5 dB at 50 GHz and ∼6.5 dB at 35 GHz, showing an inverse increase with frequency. This was consistent with updated calculations of miter bend and ohmic losses. At low frequencies (33-50 GHz), the mode purity remained very good at the exit of the waveguide, and the losses are perfectly acceptable for operation in ITER. The primary challenge may come from the future addition of a Gaussian telescope and other filter components within the corrugated guide, which will likely introduce additional perturbations to the beam profile and an increase in mode-conversion loss.
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Affiliation(s)
- G Wang
- Department of Physics and Astronomy and PSTI, UCLA, Los Angeles, California 90095, USA
| | - W A Peebles
- Department of Physics and Astronomy and PSTI, UCLA, Los Angeles, California 90095, USA
| | - E J Doyle
- Department of Physics and Astronomy and PSTI, UCLA, Los Angeles, California 90095, USA
| | - N A Crocker
- Department of Physics and Astronomy and PSTI, UCLA, Los Angeles, California 90095, USA
| | - C Wannberg
- Department of Physics and Astronomy and PSTI, UCLA, Los Angeles, California 90095, USA
| | - C Lau
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - G R Hanson
- Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA
| | - J L Doane
- General Atomics, P.O. Box 85608, San Diego, California 92186-5608, USA
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Kumar A, Lau C, Chan S, Ma M, Kearns W. A LONGITUDINAL STUDY OF THE NAVIGATION PATTERNS OF DEMENTIA PATIENTS AND THEIR RELATIONSHIP TO MMSE. Innov Aging 2017. [DOI: 10.1093/geroni/igx004.908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- A. Kumar
- Joint NTU-UBC Research Centre of Excellence in Active Living for the Elderly, Singapore, Singapore,
- IGS, Nanyang Technological University, Singapore, Singapore,
| | - C. Lau
- SCSE, Nanyang Technological University, Singapore, Singapore,
| | - S. Chan
- College of Professional and Continuing Education, Singapore, Singapore,
| | - M. Ma
- EEE, Nanyang Technological University, Singapore, Singapore,
| | - W. Kearns
- University of South Florida, Tampa, Florida
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Huang L, Injac SG, Zhao H, Lin Q, Kogiso M, Man C, Li X, Lau C, Wong ST. P11.08 Systematic drug repurposing for faster cures of pediatric cancer identifies that Digoxin prolongs survival in a PDOX model of group 4 medulloblastoma. Neuro Oncol 2017. [DOI: 10.1093/neuonc/nox036.352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Abstract
BACKGROUND The integrity of a mother-infant dyad is essential for the proper development of maternal behavior and infant growth/ development. At present, there is a lack of objective approaches to monitor mother-infant behavioral exchanges. OBJECTIVES This is an exploratory prospective study designed to evaluate the Mother-Infant Mutualistic Screening Scale (MIMSS), a novel observational tool focused on monitoring the mutual/ reciprocal sensitivity and responsiveness that mother and infant express toward one another's behaviors/ actions during the obligatory setting of daily meal times. METHODS Mother-infant interactions were assessed from videotaped feeding sessions conducted under recurrent naturalistic observations. Data were collected from 27 mother-preterm infant singleton dyads at 6 and 12 month corrected age (CA). Four levels of MIMSS are defined: Level I - both mother and infant are not responsive (NR) to one another's actions; Level II - mother is not responsive (NR) to infant, but infant is responsive (R) to mother; Level III - mother is responsive (R) to infant, but infant is not responsive (NR) to mother; Level IV - both mother and infant are responsive (R) to one another. RESULTS Inter- and intra-rater reliability between two raters was 93% and ≥ 85%, respectively. At 6 and 12 month CA, 78% and 81% of the dyads were at a MIMSS Level IV, respectively. A change in mother-infant reciprocal behavioral responses or MIMSS levels was observed in 9 of the dyads between these two ages. No association was observed between MIMSS levels and infant growth/ development as monitored by percentile Weight, Length, and Weight by Length at both corrected ages. CONCLUSIONS The MIMSS is easy to use with high inter- and intra-rater reliabilities. With the ability to differentiate between mother and infant reciprocal behavioral responses toward one another's actions, MIMSS can help health professionals assess the quality of mother-infant interactions and identify the partner(s) who may benefit from individualized assistance. Although MIMSS uses mealtime as a recurrent setting, it offers a conceptual frame work for evaluating co-regulatory processes under different contexts.
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Affiliation(s)
- Emily Zimmerman
- Department of Communication Sciences & Disorders, Northeastern University, Boston, MA USA
| | - Chantal Lau
- Department of Pediatrics/Neonatology, Baylor College of Medicine, Houston, TX, USA
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Viswanathan S, Lau C, Akbari H, Hoyen C, Walsh MC. Survey and evidence based review of probiotics used in very low birth weight preterm infants within the United States. J Perinatol 2017; 37:104. [PMID: 28050019 DOI: 10.1038/jp.2016.181] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Viswanathan S, Lau C, Akbari H, Hoyen C, Walsh MC. Survey and evidence based review of probiotics used in very low birth weight preterm infants within the United States. J Perinatol 2016; 36:1106-1111. [PMID: 27583387 DOI: 10.1038/jp.2016.144] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 07/06/2016] [Accepted: 08/01/2016] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Data from multiple clinical trials, mostly conducted outside the US, indicate that probiotic prophylaxis is an effective intervention for prevention of necrotizing enterocolitis (NEC) in preterm infants. Probiotics are routinely used in many countries. However, in the US, probiotic use in preterm infants is limited (6.7% of very low birth weight (VLBW) infants in the US were exposed to probiotics in 2014, Vermont Oxford Network (VON)). Probiotic products are often considered in 'generic' terms, but considerable variation exists between commercially available probiotics in terms of their quantity and quality. The study objectives were to identify the probiotic products used in VLBW infants within the US, and to determine whether their use was supported by reliable evidence. STUDY DESIGN A phone survey of all neonatal intensive care units (NICU) participating in VON within the US was conducted between May and September 2015 to identify NICUs that are using probiotics in VLBW infants. Data was collected regarding specific probiotic brands, timing, dose and duration of probiotic use. An evidence based literature search, limited to randomized controlled trials in VLBW infants, was conducted to determine whether the use of identified probiotics were supported by reliable evidence. RESULTS There was a 70.3% (500/711) response rate to the phone survey. During the survey period, 14.0% of NICUs were using probiotics in VLBW infants (70/500). Probiotics were routinely given to all VLBW infants in 8.8% (44/500) NICUs, while it was given in selected VLBW infants in 5.2% (26/500) of NICUs. The common indications for selective use of probiotics were feeding intolerance and antibiotic use. Sixteen commercial probiotics products were identified through the phone survey. Probiotic products most commonly used were Culturelle (27.1%), Biogaia (14.3%), Gerber Soothe (14.3%) and Florababy (8.6%). The literature search identified evidence that evaluated 4/16 probiotic products identified (Culturelle, Align, Biogaia and ABC Dophilus). Only ABC Dophilus was reported to have a protective effect against NEC, but is used sparingly in US NICUs (2.9%). CONCLUSIONS The probiotics use in VLBW infants within the US is increasing, but is still limited. There was no evidence for safety or efficacy of 90% of the probiotics currently used in US NICUs, and therefore, caution is warranted.
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Affiliation(s)
- S Viswanathan
- Division of Neonatology, Department of Pediatrics, Rainbow Babies & Children's Hospital, University Hospitals, Case Western Reserve University, Cleveland, OH, USA
| | - C Lau
- Division of Neonatology, Department of Pediatrics, Rainbow Babies & Children's Hospital, University Hospitals, Case Western Reserve University, Cleveland, OH, USA
| | - H Akbari
- Division of Neonatology, Department of Pediatrics, Rainbow Babies & Children's Hospital, University Hospitals, Case Western Reserve University, Cleveland, OH, USA
| | - C Hoyen
- Division of Pediatric Infectious Diseases, Department of Pediatrics, Rainbow Babies & Children's Hospital, University Hospitals, Case Western Reserve University, Cleveland, OH, USA
| | - M C Walsh
- Division of Neonatology, Department of Pediatrics, Rainbow Babies & Children's Hospital, University Hospitals, Case Western Reserve University, Cleveland, OH, USA
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Abstract
The hospital discharge of premature infants in neonatal intensive care units is often delayed due to their inability to feed by mouth safely and competently. With immature physiologic functions, infants born prematurely cannot be expected to readily feed by mouth at the equivalent age of a third trimester of gestation as the majority of their term counterparts do. Consequently, it is crucial that health care professionals gain an adequate knowledge of the development of preterm infants' oral feeding skills so as to optimize their safety and competency as they transition to oral feeding. With a greater sensitivity toward their immature skills, we can offer these infants a safer and smoother transition to independent oral feeding than is currently observed. This review article is an overview of the evidence-based research undertaken over the past 2 decades on the development of very-low-birth-weight infants' oral feeding skills. The description of the different functional levels where these infants can encounter hurdles may assist caregivers in identifying a potential cause or causes for their individual patients' oral feeding difficulties.
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Affiliation(s)
- Chantal Lau
- Department of Pediatrics/Neonatology, Baylor College of Medicine, Houston, TX
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McKew J, Ashlock M, Ogilvie K, Nangle L, Taylor K, Chiang K, Mertsching E, Chang J, Moldt K, Polizzi C, Xu Z, Lo C, Lau C, Adams R, Chong E. Resolaris, a potential therapeutic for rare myopathies with an immune component. Neuromuscul Disord 2015. [DOI: 10.1016/j.nmd.2015.06.114] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Pal S, Vuong W, Zhang W, Deng J, Liu X, Ruel N, Pinnamaneni M, Twardowski P, Lau C, Yu H, Figlin R, Agarwal N, Jones J. 2572 Clinical and translational assessment of VEGFR1 as a mediator of the pre-metastatic niche: Neoadjuvant axitinib in high-risk localized prostate cancer. Eur J Cancer 2015. [DOI: 10.1016/s0959-8049(16)31391-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Lau C, Bhat K, Potak D, Schanler RJ. Oral Feeding Assessment Predicts Length of Hospital Stay in Late Preterm Infants. J Pediatr Mother Care 2015; 1:102. [PMID: 27042698 PMCID: PMC4816462] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
BACKGROUND When compared with term infants, late preterm (LP) infants have greater morbidity and mortality, longer hospital stay, and greater rate of hospital readmission. Oral feeding difficulty is one of the prominent reasons for delayed discharge in LP infants. OBJECTIVE To identify the maturity levels of LP infants' oral feeding skills (OFS) at the time of their first oral feeding and to determine the relationship between OFS maturity levels and length of hospital stay. METHODS OFS was assessed in 48 LP infants born between 340/7 and 356/7 weeks gestational age at the time of their first oral feeding within 24 h of birth. The intake at 5 minutes, at completion of the feeding, and the duration of feeding a 15 mL prescribed volume of milk were tabulated. Proficiency expressed as percent mL consumed in the first 5 min/15 mL prescribed and rate of milk transfer over the entire feeding (mL/min) were recorded. OFS were assessed using a novel 4-level scale defined by the combined proficiency and rate of milk transfer. RESULTS When compared with their 35-week counterparts, infants born at 34 weeks gestation had poorer OFS profiles (p = 0.035) and longer hospital stay (p < 0.001). Additionally, further analyses demonstrated that, independently, LOS was associated negatively with both GA and OFS. CONCLUSION Assessment of OFS levels in LP infants at their first oral feeding can help identify infants at risk of oral feeding issues that may delay hospital discharge. For those infants, we speculate that provision of evidence-based efficacious interventions that improve OFS may shorten hospital stay and decrease hospital re-admissions.
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Affiliation(s)
- Chantal Lau
- Baylor College of Medicine, Department of Pediatrics, Houston TX
| | - Kiran Bhat
- Neonatal-Perinatal Medicine, Cohen Children’s Medical Center of New York, New Hyde Park NY
| | - Debra Potak
- Neonatal-Perinatal Medicine, Cohen Children’s Medical Center of New York, New Hyde Park NY
| | - Richard J. Schanler
- Neonatal-Perinatal Medicine, Cohen Children’s Medical Center of New York, New Hyde Park NY
- Hofstra North Shore-LIJ School of Medicine, Hempstead NY
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49
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Abstract
Preterm infants' hospital discharge is often delayed due to their inability to feed by mouth safely and competently. No evidence-based supported guidelines are currently available for health-care professionals caring for these infants. Available interventions advocating benefits are not readily acknowledged for lack of rigorous documentation inasmuch as any improvements may ensue from infants' normal maturation. Through research, a growing understanding of the development of nutritive sucking skills has emerged, shedding light on how and why infants may encounter oral feeding difficulties due to the immaturity of specific physiologic functions. Unfortunately, this knowledge has yet to be translated to the clinical practice to improve the diagnoses of oral feeding problems through the development of relevant assessment tools and to enhance infants' oral feeding skills through the development of efficacious preventive and therapeutic interventions. This review focuses on the maturation of the various physiologic functions implicated in the transport of a bolus from the oral cavity to the stomach. Although infants' readiness for oral feeding is deemed attained when suck, swallow, and respiration are coordinated, we do not have a clear definition of what coordination implies. We have learned that each of these functions encompasses a number of elements that mature at different times and rates. Consequently, it would appear that the proper functioning of sucking, the swallow processing, and respiration need to occur at two levels: first, the elements within each function must reach an appropriate functional maturation that can work in synchrony with each other to generate an appropriate suck, swallow process, and respiration; and second, the elements of all these distinct functions, in turn, must be able to do the same at an integrative level to ensure the safe and efficient transport of a bolus from the mouth to the stomach.
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Affiliation(s)
- Chantal Lau
- Department of Pediatrics/Neonatology, Baylor College of Medicine, Houston, Tex., USA
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50
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Abstract
AIM Very low birth weight (VLBW) infants have difficulty transitioning to independent oral feeding, be they breast- or bottle-feeding. We developed a 'self-paced' feeding system that eliminates the natural presence of the positive hydrostatic pressure and internal vacuum build-up within a bottle during feeding. Such system enhanced these infants' oral feeding performance as monitored by overall transfer (OT; % ml taken/ml prescribed), rate of transfer (RT; ml/min over an entire feeding). This study hypothesizes that the improvements observed in these infants resulted from their ability to use more mature oral feeding skills (OFS). METHODS 'Feeders and growers' born between 26-29 weeks gestation were assigned to a control or experimental group fed with a standard or self-paced bottle, respectively. They were monitored when taking 1-2 and 6-8 oral feedings/day. OFS was monitored using our recently published non-invasive assessment scale that identifies 4 maturity levels based on infants' RT and proficiency (PRO; % ml taken during the first 5 min of a feeding/total ml prescribed) during bottle feeding. RESULTS Infants oral feeding outcomes, i.e., OT, RT, PRO, and OFS maturity levels were enhanced in infants fed with the self-paced vs. standard bottle (p ≤ 0.007). CONCLUSION The improved oral feeding performance of VLBW infants correlated with enhanced OFS. This study is a first to recognize that VLBW infants' true OFS are more mature than recognized. We speculate that the physical properties inherent to standard bottles that are eliminated with the self-paced system interfere with the display of their true oral feeding potential thereby hindering their overall oral feeding performance.
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Affiliation(s)
- C Lau
- Department of Pediatrics/Neonatology, Baylor College of Medicine, Houston TX USA
| | - S Fucile
- Department of Pediatrics/Neonatology, University of Florida, Gainesville FL USA
| | - R J Schanler
- Neonatal-Perinatal Medicine, Cohen Children's Medical Center of New York, New Hyde Park NY ; Hofstra North Shore Long Island Jewish School of Medicine, Hempstead NY
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