11. |
- Björk Werner, Josefin, et al.
(författare)
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Factors Influencing Need for Late ASD Closure after Neonatal Repair of Severe Pulmonary Valve Obstruction and Intact Ventricular Septum
- 2018
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Ingår i: Cardiology in the Young. - 1467-1107. ; 28:S1, s. 151-151
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Konferensbidrag (refereegranskat)abstract
- Background: In neonates with critical pulmonary stenosis (CPS) or pulmonary atresia with intact ventricular septum (PAIVS), a nonrestrictive atrial septal defect (ASD) has been speculated to improve the initial clinical course after pulmonary valvotomy (PV) but some concerns exist in terms of its potentially longterm adverse effect on the right ventricle`s (RV) growth and persistent desaturation due to right-to-left (R-L) shunt. Objective: to assess the relationship between the size of ASD and the need for post-valvotomy reinterventions. Method: Patients with PAIVS and CPS treated at our center during 2001- 2015 were reviewed. Exclusion criteria were associated cardiac malformations and hypoplastic RV deemed unsuitable for biventricular circulation. Clinical and echocardiographic data were retrieved from the hospital ́s databases. Results: In total, 48 patients (18 with PAIVS and 30 CPS) were included. The median follow-up was 5 and 8 years, respectively. One patient with PAIVS died on day 3 after surgical valvotomy and Blalock- Taussig shunt (BTs). The majority (89%) of patients with PAIVS had surgical valvotomy whereas transcatheter valvotomy was used in the majority (87%) of patients with CPS. Palliation with BTs or PDA stenting was used in 13 (72%) patients with PAIVS and in 4 (13%) patients with CPS. Reintervention within 1 month after initial repair was needed in 4 (22%) patients with PAIVS and in 4 (13%) patients with CPS. Later reinterventions were performed in in 11(61%) patients with PAIVS and in 10(33%) patients with CPS. Of these, 7 (39%) patients with PAIVS and 5 (17%) with CPS underwent ASD closure due to persistent resting desaturation. The latter did not correlate with ASD size after valvotomy (p>0.1). Initial palliation with BTs was the only variable associated with ASD device closure (p=0.04). No patient required univentricular conversion. Conclusion: Neonatal biventricular repair for severe pulmonary valve obstruction has low mortality but significant need for late reinterventions, mostly consisting of ASD closure due to clinically significant desaturation secondary to R-L shunt. The use of aorto-pulmonary shunt, probably illustrating a more severe form of RV hypoplasia, but not the size of the ASD, predicts the need for later ASD closure due to desaturation.
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12. |
- Bühler, Janica C., et al.
(författare)
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Investigating stable oxygen and carbon isotopic variability in speleothem records over the last millennium using multiple isotope-enabled climate models
- 2022
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Ingår i: Climate of the Past. - : Copernicus GmbH. - 1814-9324 .- 1814-9332. ; 18:7, s. 1625-1654
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Tidskriftsartikel (refereegranskat)abstract
- The incorporation of water isotopologues into the hydrology of general circulation models (GCMs) facilitates the comparison between modeled and measured proxy data in paleoclimate archives. However, the variability and drivers of measured and modeled water isotopologues, as well as the diversity of their representation in different models, are not well constrained. Improving our understanding of this variability in past and present climates will help to better constrain future climate change projections and decrease their range of uncertainty. Speleothems are a precisely datable terrestrial paleoclimate archives and provide well-preserved (semi-)continuous multivariate isotope time series in the lower latitudes and mid-latitudes and are therefore well suited to assess climate and isotope variability on decadal and longer timescales. However, the relationships of speleothem oxygen and carbon isotopes to climate variables are influenced by site-specific parameters, and their comparison to GCMs is not always straightforward.Here we compare speleothem oxygen and carbon isotopic signatures from the Speleothem Isotopes Synthesis and Analysis database version 2 (SISALv2) to the output of five different water-isotope-enabled GCMs (ECHAM5-wiso, GISS-E2-R, iCESM, iHadCM3, and isoGSM) over the last millennium (850–1850 CE). We systematically evaluate differences and commonalities between the standardized model simulation outputs. The goal is to distinguish climatic drivers of variability for modeled isotopes and compare them to those of measured isotopes.We find strong regional differences in the oxygen isotope signatures between models that can partly be attributed to differences in modeled surface temperature. At low latitudes, precipitation amount is the dominant driver for stable water isotope variability; however, at cave locations the agreement between modeled temperature variability is higher than for precipitation variability. While modeled isotopic signatures at cave locations exhibited extreme events coinciding with changes in volcanic and solar forcing, such fingerprints are not apparent in the speleothem isotopes. This may be attributed to the lower temporal resolution of speleothem records compared to the events that are to be detected. Using spectral analysis, we can show that all models underestimate decadal and longer variability compared to speleothems (albeit to varying extents).We found that no model excels in all analyzed comparisons, although some perform better than the others in either mean or variability. Therefore, we advise a multi-model approach whenever comparing proxy data to modeled data. Considering karst and cave internal processes, e.g., through isotope-enabled karst models, may alter the variability in speleothem isotopes and play an important role in determining the most appropriate model. By exploring new ways of analyzing the relationship between the oxygen and carbon isotopes, their variability, and co-variability across timescales, we provide methods that may serve as a baseline for future studies with different models using, e.g., different isotopes, different climate archives, or different time periods.
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13. |
- Cirenajwis, Helena, et al.
(författare)
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Molecular stratification of metastatic melanoma using gene expression profiling: prediction of survival outcome and benefit from molecular targeted therapy.
- 2015
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Ingår i: Oncotarget. - : Impact Journals, LLC. - 1949-2553. ; 6:14, s. 12297-12309
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Tidskriftsartikel (refereegranskat)abstract
- Melanoma is currently divided on a genetic level according to mutational status. However, this classification does not optimally predict prognosis. In prior studies, we have defined gene expression phenotypes (high-immune, pigmentation, proliferative and normal-like), which are predictive of survival outcome as well as informative of biology. Herein, we employed a population-based metastatic melanoma cohort and external cohorts to determine the prognostic and predictive significance of the gene expression phenotypes. We performed expression profiling on 214 cutaneous melanoma tumors and found an increased risk of developing distant metastases in the pigmentation (HR, 1.9; 95% CI, 1.05-3.28; P=0.03) and proliferative (HR, 2.8; 95% CI, 1.43-5.57; P=0.003) groups as compared to the high-immune response group. Further genetic characterization of melanomas using targeted deep-sequencing revealed similar mutational patterns across these phenotypes. We also used publicly available expression profiling data from melanoma patients treated with targeted or vaccine therapy in order to determine if our signatures predicted therapeutic response. In patients receiving targeted therapy, melanomas resistant to targeted therapy were enriched in the MITF-low proliferative subtype as compared to pre-treatment biopsies (P=0.02). In summary, the melanoma gene expression phenotypes are highly predictive of survival outcome and can further help to discriminate patients responding to targeted therapy.
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14. |
- Comas-Bru, Laia, et al.
(författare)
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Evaluating model outputs using integrated global speleothem records of climate change since the last glacial
- 2019
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Ingår i: Climate of the Past. - : Copernicus GmbH. - 1814-9324 .- 1814-9332. ; 15:4, s. 1557-1579
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Tidskriftsartikel (refereegranskat)abstract
- Although quantitative isotope data from speleothems has been used to evaluate isotope-enabled model simulations, currently no consensus exists regarding the most appropriate methodology through which to achieve this. A number of modelling groups will be running isotope-enabled palaeoclimate simulations in the framework of the Coupled Model Intercomparison Project Phase 6, so it is timely to evaluate different approaches to using the speleothem data for data-model comparisons. Here, we illustrate this using 456 globally distributed speleothem delta O-18 records from an updated version of the Speleothem Isotopes Synthesis and Analysis (SISAL) database and palaeoclimate simulations generated using the ECHAM5-wiso isotope-enabled atmospheric circulation model. We show that the SISAL records reproduce the first-order spatial patterns of isotopic variability in the modern day, strongly supporting the application of this dataset for evaluating model-derived isotope variability into the past. However, the discontinuous nature of many speleothem records complicates the process of procuring large numbers of records if data-model comparisons are made using the traditional approach of comparing anomalies between a control period and a given palaeoclimate experiment. To circumvent this issue, we illustrate techniques through which the absolute isotope values during any time period could be used for model evaluation. Specifically, we show that speleothem isotope records allow an assessment of a model's ability to simulate spatial isotopic trends. Our analyses provide a protocol for using speleothem isotope data for model evaluation, including screening the observations to take into account the impact of speleothem mineralogy on delta O-18 values, the optimum period for the modern observational baseline and the selection of an appropriate time window for creating means of the isotope data for palaeo-time-slices.
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15. |
- Dodel, Richard C., et al.
(författare)
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Measurement of costs and scales for outcome evaluation in health economic studies of Parkinson's disease
- 2014
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Ingår i: Movement Disorders. - : Wiley. - 0885-3185. ; 29:2, s. 169-176
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Health economic studies in Parkinson's disease (PD) have become increasingly common in recent years. Because several methodologies and instruments have been used to assess cost and outcomes in PD, the Movement Disorder Society (MDS) commissioned a Task Force to assess their properties and make recommendations regarding their use. A systematic literature review was conducted to explore the use of those instruments in PD and to determine which should be selected for this review. We assessed approaches to evaluate cost of illness (COI), cost effectiveness, and cost utilities, which include the use of direct (standard gamble, time trade-off. and visual analogue scales) and indirect instruments to measure health status and utilities. No validated instruments/models were identified for the evaluation of COI or cost-effectiveness in patients with PD; therefore, no instruments in this group are recommended. Among utility instruments, only a few of these outcome instruments have been used in the PD population, and only limited psychometric data are available for these instruments with respect to PD. Because psychometric data for further utility instruments in conditions other than PD already exist, the standard gamble and time trade-off methods and the EQ-5D (a European quality-of-life health states instrument) and Health Utility Index instruments met the criteria for scales that are "recommended (with limitations)," but only the EQ-5D has been assessed in detail in PD patients. The MDS Task Force recommends further study of these instruments in the PD population to establish core psychometric properties. For the assessment of COI, the Task Force considers the development of a COI instrument specifically for PD, like that available for Alzheimer's disease. © 2013 Movement Disorder Society.
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16. |
- Erard, Margot, et al.
(författare)
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Left atrial strain in patients after arterial switch operation for transposition of the great arteries
- 2023
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Ingår i: Acta Cardiologica. - 0001-5385 .- 0373-7934.
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Tidskriftsartikel (refereegranskat)abstract
- Background: Left atrial (LA) strain, comprising LA reservoir, conduit and contractile function could add mechanistic information of patients after arterial switch operation (ASO) for transposition of the great arteries (TGA). ASO patients might have abnormal ventriculoarterial coupling, which makes them vulnerable to left ventricle (LV) dysfunction and results in reduced exercise capacity. This explorative study aimed to evaluate the relation between LA strain, atrial size, ventricular function, and exercise data obtained by cardiopulmonary exercise testing (CPET). Methods: In a cohort of 44 patients (71% male, mean age 25 ± 4 years) LA strain was measured using transthoracic speckle-tracking echocardiography. Further assessment involved standard echocardiography, CPET evaluation, and blood sampling. LA strain values were compared to normal values. Correlations were calculated. Regression analysis with all strain variables to the CPET data was performed. Results: LA reservoir, conduit and contractile strain were normal in 30%, 89% and 50% of the patients, respectively. LA reservoir/contractile strain correlated to LV ejection fraction (ρ 0.310/−0.159, respectively) and LA reservoir/conduit strain correlated to the LA volume index (ρ 0.336/−0.357, respectively). None of the individual LA strain parameters were associated with the CPET variables. In multivariate regression analysis, LA contractile strain was significantly associated with the percentage of predicted maximal heart rate (β − 2.555). Conclusions: These data suggest that in TGA patients after ASO repair LA strain is impaired and correlates with LA size and LV function. However, impaired LA strain wasn’t associated with the standard CPET parameters. As such, clinical significance needs to be further unravelled.
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17. |
- Feng, Yi, et al.
(författare)
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Characterization of Inkjet Printed Coplanar Waveguides for Flexible Electronics
- 2011
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Ingår i: NIP27: International Conference on Digital Printing Technologies and Digital Fabrication 2011. - : The Society for Imaging Science and Technology. - 9780892082964 ; , s. 454-457
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Konferensbidrag (refereegranskat)abstract
- The low conductivity and thin layers of the inkjet-printed metal conductors have always been a big concern in paper-based printed electronics for high frequency applications. To provide the fundamental knowledge, the high frequency characteristics of inkjet-printed coplanar waveguides on paper substrate were studied experimentally in terms of characteristic impedance and conductor losses using the time domain reflectometry technique. The influences of different printing settings and of geometric parameters on the waveguide's properties were investigated. Considering the measurement accuracy in high frequency characterization, one sample with an impedance of 51.2Ω was achieved. The electrical stability of the samples was also studied and explained. In addition, one waveguide sample was printed in a way that the pattern area with the highest current density is thickened. This variable ink-layer thickness approach has successfully been proven as a promising solution to reduce the conductor losses and yet consuming less ink.
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18. |
- Gabriels, Charlien, et al.
(författare)
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Serial pulmonary vascular resistance assessment in patients late after ventricular septal defect repair.
- 2019
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Ingår i: International journal of cardiology. - : Elsevier BV. - 1874-1754 .- 0167-5273. ; 282, s. 38-43
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Tidskriftsartikel (refereegranskat)abstract
- The long-term evolution of pulmonary vascular resistance (PVR) after ventricular septal defect (VSD) repair is unknown. This study serially evaluated resting and exercise PVR after VSD repair in childhood.Patients were enrolled from the outpatient Adult Congenital Heart Disease clinic of the University Hospitals Leuven and compared to age- and gender-matched controls. Participants underwent resting and exercise echocardiography and cardiopulmonary exercise testing at baseline and follow-up. Total PVR was calculated as the ratio of mean pulmonary artery pressure (mPAP) to cardiac output (CO). The slope of the mPAP-CO curve (exercise PVR) was obtained using linear regression analysis.Twenty-seven patients (mean age 31±7years, 70% male) and 18 controls were included. At baseline, patients had larger right ventricular (RV) end-diastolic areas (10±2 vs 9±1cm2/m2, p=0.001) and lower tricuspid annular plane systolic excursion (TAPSE) (17 (17-19) vs 26 (22-28) mm, p<0.001). After 1.1 (1.0-1.5) years follow-up, similar differences in RV areas and TAPSE were found. Patients reached lower peak workload and cardiac index compared to controls at each time point. Peak total PVR was higher (Baseline: 2.7±0.8 vs 2.2±0.3mmHg/L/min, p=0.005; Follow-up: 2.9±0.9 vs 2.1±0.3mmHg/L/min, p<0.001) and the mPAP-CO slope was steeper (Baseline: 2.2±0.8 vs 1.7±0.3mmHg/L/min, p=0.008; Follow-up: 2.5±0.9 vs 1.6±0.3mmHg/L/min, p<0.001) in patients. The mPAP-CO slope in patients correlated inversely with peak oxygen uptake (R=-0.41 and-0.45, p=0.036 and 0.022, baseline and follow-up, respectively).Despite repair, VSD patients seem to show altered pulmonary hemodynamics and RV impairment at rest and exercise, supporting life-long follow-up.
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19. |
- Greczynski, Grzegorz, et al.
(författare)
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Metal versus rare-gas ion irradiation during Ti1-xAlxN film growth by hybrid high power pulsed magnetron/dc magnetron co-sputtering using synchronized pulsed substrate bias
- 2012
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Ingår i: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films. - : American Vacuum Society. - 0734-2101 .- 1520-8559. ; 30:6
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Tidskriftsartikel (refereegranskat)abstract
- Metastable NaCl-structure Ti1-xAlxN is employed as a model system to probe the effects of metal versus rare-gas ion irradiation during film growth using reactive high-power pulsed magnetron sputtering (HIPIMS) of Al and dc magnetron sputtering of Ti. The alloy film composition is chosen to be x = 0.61, near the kinetic solubility limit at the growth temperature of 500 degrees C. Three sets of experiments are carried out: a -60V substrate bias is applied either continuously, in synchronous with the full HIPIMS pulse, or in synchronous only with the metal-rich-plasma portion of the HIPIMS pulse. Alloy films grown under continuous dc bias exhibit a thickness-invariant small-grain, two-phase nanostructure (wurtzite AlN and cubic Ti1-xAlxN) with random orientation, due primarily to intense Ar+ irradiation leading to Ar incorporation (0.2 at. %), high compressive stress (-4.6 GPa), and material loss by resputtering. Synchronizing the bias with the full HIPIMS pulse results in films that exhibit much lower stress levels (-1.8GPa) with no measureable Ar incorporation, larger grains elongated in the growth direction, a very small volume fraction of wurtzite AlN, and random orientation. By synchronizing the bias with the metal-plasma phase of the HIPIMS pulses, energetic Ar+ ion bombardment is greatly reduced in favor of irradiation predominantly by Al+ ions. The resulting films are single phase with a dense competitive columnar structure, strong 111 orientation, no measureable trapped Ar concentration, and even lower stress (-0.9 GPa). Thus, switching from Ar+ to Al+ bombardment, while maintaining the same integrated incident ion/metal ratio, eliminates phase separation, minimizes renucleation during growth, and reduces the high concentration of residual point defects, which give rise to compressive stress.
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20. |
- Karam, Elias, et al.
(författare)
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Endoscopic and Surgical Management of Non-Metastatic Ampullary Neuroendocrine Neoplasia : A Multi-Institutional Pancreas2000/EPC Study
- 2023
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Ingår i: Neuroendocrinology. - 0028-3835. ; 113:10, s. 1024-1034
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Ampullary neuroendocrine neoplasia (NEN) is rare and evidence regarding their management is scarce. This study aimed to describe clinicopathological features, management, and prognosis of ampullary NEN according to their endoscopic or surgical management. Methods: From a multi-institutional international database, patients treated with either endoscopic papillectomy (EP), transduodenal surgical ampullectomy (TSA), or pancreaticoduodenectomy (PD) for ampullary NEN were included. Clinical features, post-procedure complications, and recurrences were assessed. Results: 65 patients were included, 20 (30.8%) treated with EP, 19 (29.2%) with TSA, and 26 (40%) with PD. Patients were mostly asymptomatic (n = 46; 70.8%). Median tumor size was 17 mm (12-22), tumors were mostly grade 1 (70.8%) and pT2 (55.4%). Two (10%) EP resulted in severe American Society for Gastrointestinal Enterology (ASGE) adverse post-procedure complications and 10 (50%) were R0. Clavien 3-5 complications did not occur after TSA and in 4, including 1 postoperative death (15.4%) of patients after PD, with 17 (89.5%) and 26 R0 resection (100%), respectively. The pN1/2 rate was 51.9% (n = 14) after PD. Tumor size larger than 1 cm (i.e., pT stage >1) was a predictor for R1 resection (p < 0.001). Three-year overall survival and disease-free survival after EP, TSA, and PD were 92%, 68%, 92% and 92%, 85%, 73%, respectively. Conclusion: Management of ampullary NEN is challenging. EP should not be performed in lesions larger than 1 cm or with a endoscopic ultrasonography T stage beyond T1. Local resection by TSA seems safe and feasible for lesions without nodal involvement. PD should be preferred for larger ampullary NEN at risk of nodal metastasis.
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