Open boundary conditions were developed for atmospheric large-eddy simulation (LES) models and implemented into the Dutch Atmospheric Large-Eddy Simulation model. The implementation was tested in a ...“Big Brother”-like setup, in which the simulation with open boundary conditions was forced by an identical control simulation with periodic boundary conditions. The results show that the open boundary implementation has minimal influence on the solution. Both the mean state and the turbulent structures are close to the control simulation, and disturbances at the in- and outflow boundaries are negligible. To emulate a setup in which the LES is coupled to a coarser model, the influence of coarse boundary input was tested by smoothing the output of the periodic control simulation both temporally and spatially before feeding it as input to the simulation with open boundary conditions. When smoothing is applied over larger spatial and longer temporal scales, disturbances start to form at the inflow boundary and an area exists where turbulence needs to develop. Adding synthetic turbulence to the smoothed input reduces the size of this area and the magnitude of the disturbances.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
The aim of this verification study was to compare the QuantiFERON®-TB Gold Plus (QFT-Plus) to the QuantiFERON®-TB Gold In Tube (QFT-GIT). The new QFT-Plus test contains an extra antigen tube which, ...according to the manufacturer additionally elicits a CD8+ T-cell response above the CD4+ T-cell response. We assessed the value of this tube in detecting recent latent tuberculosis infections.
Between May 2015 and December 2016, 1031 subjects underwent QFT-Plus and QFT-GIT test. Overall agreement between both tests and performance for different test indications and/or immune states was assessed. A difference of >0.6 IU/mL interferon-γ release between the two antigen tubes of the QFT-Plus assay was considered a true difference and used as estimation for CD8+ T-cell response.
Analysis of the QuantiFERON tests resulted in an overall agreement between assays of 95%. Subjects considered to be recently exposed to tuberculosis had significantly more often a true difference in interferon-γ release compared to all other subjects (p = 0.029).
Results of QFT-Plus are highly comparable to QFT-GIT. Although there is an indication that a true difference in interferon-γ release between the antigen tubes is associated with recent latent tuberculosis infection, the QFT-Plus could not be used to exclude recent exposure.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Introduction Silver-coated grafts are designed to prevent vascular graft infections. Silver is a safe element but toxic effects have been reported. We describe two cases of possible localized argyria ...after silver graft implantation. Report Two patients presented with perigraft groin collections after implantation of silver grafts. During reoperation, an ashen-grey necrotic substance was seen surrounding the grafts. The grafts were explanted and lower limb perfusion restored. Cultures were negative and both patients had uneventful recoveries. Discussion Our cases are highly suggestive of a possible unique adverse effect: a combination of localized silver toxicity and neutrophilic mediated tissue destruction.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Inguinal hernia belongs to the most common surgical pathology worldwide. Approximately, one third is asymptomatic. The value of watchful waiting (WW) in patients with asymptomatic or mildly ...symptomatic inguinal hernia has been established in a few randomised controlled trials (RCTs). The aim of this study was to assess long-term outcomes of a RCT comparing WW and elective surgery.
In the original study, men aged ≥50 years with an asymptomatic or mildly symptomatic inguinal hernia were randomly assigned to WW or elective repair. In the present study, the primary outcome was the 12-year crossover rate to surgery, secondary outcomes were time-to-crossover, patient regret, pain, quality of life and incarceration. Dutch Trial Registry: NTR629.
Out of 496 originally analysed patients, 488 (98.4%) were evaluable for chart review (WW: n = 258, surgery: n = 230), and 200 (41.0%) for telephone contact (WW: n = 106, surgery: n = 94) between November 2021 and March 2022 with a median 12 years follow-up (IQR 9–14). After 12 years, the estimated cumulative crossover rate to surgery was 64.2%, which was higher in mildly symptomatic than in asymptomatic patients (71.7% versus 60.4%, HR 1.451, 95% CI: 1.064–1.979). Time-to-crossover was longer in asymptomatic patients (50% after 6.0 years versus 2.0 years, p = 0.019). Patient regret was higher in the WW group (37.7 versus 18.0%, p = 0.002), as well as pain/discomfort (p = 0.031). Quality of life did not differ (p = 0.737). In the WW group, incarceration occurred in 10/255 patients (3.9%).
During 12-year follow-up, most WW patients crossed over to surgery, significantly earlier with mildly symptomatic hernia. Considering the relatively low incarceration rate, WW might still be an option in asymptomatic patients with a clear preference and being well-informed about pros and cons.
The initial trial was funded by the Netherlands Organisation for Health Research and Development (ZonMW). This long-term study did not receive funding.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Although early vascular complications of the Angio-Seal closure device have been well described, little is known about late vascular complications due to this device. The aim of this paper is to ...discuss late femoral stenosis associated with the use of the Angio-Seal closure device. A literature search was performed using Medline', Embase' and The Cochrane Library' to identify relevant articles published up to the first of May 2007. Late occlusion was defined as an occlusion after approximately one week after Angio-Seal deployment. All together, eleven relevant papers were available. The reported prevalence of late vascular stenosis associated with Angio-Seal use varies between 1/961 and 4/175. Claudication was the most frequently reported complaint. In most cases, late stenosis due to the use of the Angio-Seal required surgery. Vascular obstruction due to the device has been reported up to 6 months after placement. In conclusion, vascular stenosis due to the use an Angio-Seal closure device is a complication that not only occurs in the first few days after placement, but also in the following months. In every patient developing complaints of arterial insufficiency after using an Angio-Seal, local arterial stenosis due to the device should be considered in the differential diagnosis. It therefore is important to register the use of the device in the patient chart.
Objective. To assess the accuracy of dobutamine stress myocardial perfusion single photon emission computed tomographic imaging (SPECT) for the diagnosis of vascular stenosis after coronary artery ...bypass grafting (CABG).
Background. Exercise thallium scintigraphy is a clinically useful method for the diagnosis of graft stenosis after CABG. Although dobutamine perfusion scintigraphy is an alternative method for the evaluation of patients with limited exercise capacity, its value in the diagnosis of vascular stenosis after CABG has not been studied.
Methods. Dobutamine (up to 40 μg/kg/min)-atropine (up to 1 mg) stress test in conjunction with myocardial perfusion SPECT imaging (
201Tl or 99m technetium sestamibi MIBI) was performed in 71 patients (mean age 58 ± 9 years, 57 men) with limited exercise capacity referred for evaluation of myocardial ischemia 3.7 ± 3.5 years after CABG. Significant vascular stenosis was defined as ≥50% luminal diameter stenosis of a graft or a native nongrafted coronary artery and was predicted on the basis of reversible perfusion abnormalities.
Results. Significant vascular stenosis was detected in 52 patients. Sensitivity, specificity, and accuracy of reversible perfusion defects at dobutamine SPECT for the overall diagnosis of vascular stenosis were 81%, confidence interval (CI) 72 to 90, 79%, CI 69 to 88, and 80%, CI 71 to 90, respectively. Significant vascular stenosis was detected in 73 arterial regions. Sensitivity, specificity, and accuracy of dobutamine SPECT for the diagnosis of regional vascular stenosis were 66%, CI 58 to 74, 83%, CI 76 to 89, and 74%, CI 67 to 81, respectively. Patients with multivessel stenosis had a higher number of ischemic segments (1.6 ± 1.3 vs 1 ± 1,
P < .05) and ischemic perfusion score (3.2 ± 2.7 vs 2.2 ± 2.3,
P < .05) than patients with single-vessel stenosis, respectively. Significant graft stenosis was detected in 67 graft regions. Sensitivity, specificity, and accuracy of dobutamine SPECT for the diagnosis of regional graft stenosis were 64%, CI 56 to 73, 85%, CI 78 to 91, and 74%, CI 66 to 82, respectively.
Conclusion. Dobutamine stress myocardial perfusion SPECT imaging is a useful method for the diagnosis of significant vascular stenosis after CABG in patients with limited exercise capacity. (J Nucl Cardiol 1998;5:491–497)
Full text
Available for:
EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The Cavitron Ultrasonic Surgical Aspirator (CUSA) (Cooper Medical, Stamford, CT) is a relatively new surgical modality. The risk of tumor seeding during tumor surgery has not been studied until now. ...Hanks balanced salt solution, normal saline, distilled water, and Dakin's solution were used as irrigation fluids during CUSA fragmentation of Lewis lung carcinoma in C57BI/10 female mice, using the machine at 40% of its maximal output. All four irrigation fluids contained viable tumor cells—growing in vitro as well as in vivo—after tumor aspiration. Normal saline was also used when the machine was operating at its maximal output. Under these conditions, the irrigation fluid contained viable tumor cells as well.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Dobutamine-induced hypotension has been disregarded as a marker of more severe functional abnormalities in patients with suspected coronary artery disease. However, its functional significance in ...patients with myocardial infarction has not been studied. The aim of this study was to define the predictors of systolic blood pressure (SBP) response to dobutamine in patients with previous myocardial infarction. Dobutamine stress (up to 40 microg/kg per minute) echocardiography was performed in 326 patients with prior myocardial infarction referred for evaluation of myocardial ischemia. A 16-segment, four-grade score model was used to assess left ventricular function. Wall motion score index was derived by summation of wall motion score divided by 16. SBP and heart rate increased from rest to peak dobutamine stress (127 +/- 22 vs 134 +/- 27 mm Hg and 72 +/- 14 vs 122 +/- 24 bpm, p < 0.00001 in both). An increase of SBP > or = 30 mm Hg occurred in 50 patients (15%). By multivariate analysis, independent predictors of failure of SBP increase were higher peak wall motion score index (p < 0.001), higher resting SBP (p < 0.01), and medication with calcium channel blockers (p < 0.05). SBP drop > or = 20 mm Hg occurred in 54 patients (17%). Independent predictors of SBP drop were higher resting wall motion score index (p < 0.001), higher resting SBP (p < 0.0001), and older age (p < 0.05). In patients with myocardial infarction, left ventricular function and baseline systolic blood pressure are powerful predictors of SBP response to dobutamine stress testing.
PDF
