80 results on '"Bache S"'
Search Results
2. MircoRNA-9-3p: a novel predictor of neurological outcome after cardiac arrest
- Author
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Paulin Beske, R, primary, Bache, S, additional, Olsen, MH, additional, Rossing, M, additional, Nielsen, FC, additional, Meyer, MAS, additional, Moeller, K, additional, Kjaergaard, J, additional, Jeppesen, JB, additional, Nielsen, N, additional, and Hassager, C, additional
- Published
- 2022
- Full Text
- View/download PDF
3. Problems in obtaining sufficient anaesthesia with propofol and remifentanil: three cases, a test infusion, and a review
- Author
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Bache, S., Stendell, L., Olsen, N. V., and Olsen, K. S.
- Published
- 2013
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4. Verification of endotracheal intubation in obese patients – temporal comparison of ultrasound vs. auscultation and capnography
- Author
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Pfeiffer, P., Bache, S., Isbye, D. L., Rudolph, S. S., Rovsing, L., and Brglum, J.
- Published
- 2012
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5. Effects of Adductor-Canal-Blockade on pain and ambulation after total knee arthroplasty: a randomized study
- Author
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JENSTRUP, M. T., JÆGER, P., LUND, J., FOMSGAARD, J. S., BACHE, S., MATHIESEN, O., LARSEN, T. K., and DAHL, J. B.
- Published
- 2012
- Full Text
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6. Anaphylaxis to ethylene oxide – a rare and overlooked phenomenon?
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Bache, S., Petersen, J. T., and Garvey, L. H.
- Published
- 2011
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7. SU-G-206-08: How Should Focal Spot Be Chosen for Optimized CT Imaging with Dose Modulation?
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Bache, S, primary, Liu, X, additional, and Rong, J, additional
- Published
- 2016
- Full Text
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8. SU‐G‐206‐02: Impact of Focal Spot Sizes On CT Image Quality
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Bache, S, primary and Rong, J, additional
- Published
- 2016
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9. TH-CD-207B-12: Quantification of Clinical Feedback On Image Quality Differences Between Two CT Scanner Models
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Bache, S, primary, Liu, X, additional, Loyer, E, additional, and Rong, J, additional
- Published
- 2016
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10. Universal decontamination of hospital surfaces in an occupied inpatient room with a continuous 405 nm light source.
- Author
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Bache, S E, Maclean, M, Gettinby, G, Anderson, J G, MacGregor, S J, and Taggart, I
- Abstract
Background: Previous work has shown that a ceiling-mounted, 405 nm high-intensity narrow-spectrum light environmental decontamination system (HINS-light EDS) reduces bacterial contamination of environmental surfaces in a burns unit by between 27% and 75%. Examination of the efficacy of the light over extended exposure times and its probable mode of action was performed.Aim: To ascertain the correlation between bacterial kill achieved on sampled surface sites around the burns unit and both irradiance levels of the 405 nm light, and exposure time.Methods: Seventy samples were taken using contact agar plates from surfaces within an occupied side-room in the burns unit before, during, and after a seven-day use of the HINS-light EDS. This was repeated in three separate studies. Statistical analysis determined whether there was significant decrease in environmental contamination during prolonged periods of HINS-light treatment, and whether there was an association between irradiance and bacterial kill.Findings: A decrease of between 22% and 86% in the mean number of surface bacteria was shown during the use of the HINS-light EDS. When the light ceased to be used, increases of between 78% and 309% occurred. There was no correlation between bacterial kill and irradiance levels at each sampling site but strong correlation between bacterial kill and exposure time.Conclusion: Prolonged exposure to the HINS-light EDS causes a cumulative decontamination of the surfaces within a burns unit. The importance of exposure time and possible airborne effect over irradiance levels is emphasized. [ABSTRACT FROM AUTHOR]- Published
- 2018
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11. SU-E-I-22: A Comprehensive Investigation of Noise Variations Between the GE Discovery CT750 HD and GE LightSpeed VCT
- Author
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Bache, S, primary, Loyer, E, additional, Stauduhar, P, additional, Liu, X, additional, and Rong, J, additional
- Published
- 2015
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12. Investigation of a low-cost optical-CT system with minimal refractive index-matching fluid
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Bache, S, primary, Malcolm, J, additional, Adamovics, J, additional, and Oldham, M, additional
- Published
- 2015
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13. SU-C-BRE-04: Microbeam-Radiation-Therapy (MRT): Characterizing a Novel MRT Device Using High Resolution 3D Dosimetry
- Author
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Li, Q, primary, Juang, T, additional, Bache, S, additional, Chang, S, additional, and Oldham, M, additional
- Published
- 2014
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14. SU‐E‐J‐164: An Investigation of a Low‐Cost ‘dry’ Optical‐CT Scanning System for 3D Dosimetry
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Bache, S, primary, Malcolm, J, additional, Adamovics, J, additional, and Oldham, M, additional
- Published
- 2014
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15. WE-F-16A-04: Micro-Irradiator Treatment Verification with High-Resolution 3D-Printed Rodent-Morphic Dosimeters
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Bache, S, primary, Belley, M, additional, Benning, R, additional, Stanton, I, additional, Therien, M, additional, Yoshizumi, T, additional, Adamovics, J, additional, and Oldham, M, additional
- Published
- 2014
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16. Investigating end-to-end accuracy of image guided radiation treatment delivery using a micro-irradiator
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Rankine, L J, primary, Newton, J, additional, Bache, S T, additional, Das, S K, additional, Adamovics, J, additional, Kirsch, D G, additional, and Oldham, M, additional
- Published
- 2013
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17. WE-E-108-09: An Investigation of the Feasibility of Rodentmorphic 3D Dosimeters for Verification of Precision Micro-Irradiator Treatment
- Author
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Bache, S, primary, Juang, T, additional, Adamovics, J, additional, Benning, R, additional, Koontz, B, additional, Predmore, K, additional, Dewhirst, M, additional, and Oldham, M, additional
- Published
- 2013
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18. Anaphylaxis to ethylene oxide - a rare and overlooked phenomenon?
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Bache, S., primary, Petersen, J. T., additional, and Garvey, L. H., additional
- Published
- 2011
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19. A symphony of maladies
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Bache, S., primary and Edenborough, F., additional
- Published
- 2008
- Full Text
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20. MircoRNA-9-3p: a novel predictor of neurological outcome after cardiac arrest.
- Author
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Beske, R Paulin, Bache, S, Olsen, MH, Rossing, M, Nielsen, FC, Meyer, MAS, Moeller, K, Kjaergaard, J, Jeppesen, JB, Nielsen, N, and Hassager, C
- Published
- 2022
- Full Text
- View/download PDF
21. AN IMMIGRANT EXPLORATION OF THE MIDDLE WEST IN 1839
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JOHANSEN, JOHANNES, primary, BACHE, S�REN, additional, and Study, The, additional
- Published
- 1944
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22. Genetic regulation of nascent RNA maturation revealed by direct RNA nanopore sequencing.
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Choquet K, Chaumont LP, Bache S, Baxter-Koenigs AR, and Churchman LS
- Abstract
Quantitative trait loci analyses have revealed an important role for genetic variants in regulating alternative splicing (AS) and alternative cleavage and polyadenylation (APA) in humans. Yet, these studies are generally performed with mature mRNA, so they report on the outcome rather than the processes of RNA maturation and thus may overlook how variants directly modulate pre-mRNA processing. The order in which the many introns of a human gene are removed can substantially influence AS, while nascent RNA polyadenylation can affect RNA stability and decay. However, how splicing order and poly(A) tail length are regulated by genetic variation has never been explored. Here, we used direct RNA nanopore sequencing to investigate allele-specific pre-mRNA maturation in 12 human lymphoblastoid cell lines. We found frequent splicing order differences between alleles and uncovered significant single nucleotide polymorphism (SNP)-splicing order associations in 17 genes. This included SNPs located in or near splice sites as well as more distal intronic and exonic SNPs. Moreover, several genes showed allele-specific poly(A) tail lengths, many of which also had a skewed allelic abundance ratio. HLA class I transcripts, which encode proteins that play an essential role in antigen presentation, showed the most allele-specific splicing orders, which frequently co-occurred with allele-specific AS, APA or poly(A) tail length differences. Together, our results expose new layers of genetic regulation of pre-mRNA maturation and highlight the power of long-read RNA sequencing for allele-specific analyses.
- Published
- 2024
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23. A systematic task-based image quality assessment of photon-counting and energy integrating CT as a function of reconstruction kernel and phantom size.
- Author
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Bhattarai M, Bache S, Abadi E, and Samei E
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- Humans, Tomography Scanners, X-Ray Computed, Phantoms, Imaging, Algorithms, Radiation Dosage, Tomography, X-Ray Computed methods, Iodine
- Abstract
Background: Image quality of photon-counting and energy integrating CT scanners changes with object size, dose to the object, and kernel selection., Purpose: To comprehensively compare task-generic image quality of photon-counting CT (PCCT) and energy integrating CT (EICT) systems as a function of phantom size, dose, and reconstruction kernel., Methods: A size-variant phantom (Mercury Phantom 3.0) was used to characterize the image quality of PCCT and EICT systems as a function of object size. The phantom contained five cylinders attached by slanted tapered sections. Each cylinder contained two sections: one uniform for noise, and the other with inserts for spatial resolution and contrast measurements. The phantom was scanned on Siemens' SOMATOM Force and NAEOTOM Alpha at 1.18 and 7.51 mGy without tube current modulation. CTDI
vol was matched across two systems by setting the required tube currents, else, all other acquisition settings were fixed. CT sinograms were reconstructed using FBP and iterative (ADMIRE2 - Force; QIR2 - Alpha) algorithms with Body regular (Br) kernels. Noise Power Spectrum (NPS), Task Transfer Function (TTF), contrast-to-noise ratio (CNR), and detectability index (d') for a task of identifying 2-mm disk were evaluated based on AAPM TG-233 metrology using imQuest, an open-source software package. Averaged noise frequency (fav ) and 50% cut-off frequency for TTF (f50 ) were used as scalar metrics to quantify noise texture and spatial resolution, respectively. The difference between image quality metrics' measurements was calculated as IQPCCT - IQEICT ., Results: From Br40 (soft) to Br64 (sharp), f50 for air insert increased from 0.35 mm-1 ± 0.04 (standard deviation) to 0.76 mm-1 ± 0.17, 0.34 mm-1 ± 0.04 to 0.77 mm-1 ± 0.17, 0.37 mm-1 ± 0.02 to 0.95 mm-1 ± 0.17 for PCCT-T3D-QIR2, PCCT-70keV-QIR2, and EICT-ADMIRE2, respectively, when averaged over all sizes and dose levels. Similarly, from Br40 to Br64, noise magnitude increased from 10.86 HU ± 7.12 to 38.61 HU ± 18.84, 10.94 HU ± 7.08 to 38.82 HU ± 18.70, 13.74 HU ± 11.02 to 52.11 HU ± 26.22 for PCCT-T3D-QIR2, PCCT-70keV-QIR2, and EICT-ADMIRE2, respectively. The difference in fav was consistent across all sizes and dose levels. PCCT-70keV-VMI showed better consistency in contrast measurements for iodine and bone inserts than PCCT-T3D and EICT; however, PCCT-T3D had higher contrast for both inserts. From Br40 to Br64, considering all sizes and dose levels, CNR for iodine insert decreased from 52.30 ± 46.44 to 12.18 ± 10.07, 40.42 ± 33.42 to 9.48 ± 7.16, 39.94 ± 37.60 to 7.84 ± 6.67 for PCCT-T3D-QIR2, PCCT-70keV-QIR2, and EICT-ADMIRE2, respectively., Conclusions: Both PCCT image types, T3D and 70-keV-VMI exhibited similar or better noise, contrast, CNR than EICT when comparing kernels with similar names. For 512 × 512 matrix, PCCT's sharp kernels had lower resolution than EICT's sharp kernels. For all image quality metrics, except extreme low, every dose condition had a similar set of IQ-matching kernels. It suggests that considering patient size and dose level to determine IQ-matching kernel pairs across PCCT and EICT systems may not be imperative while translating protocols, except when the signal to the detector is extremely low., (© 2023 American Association of Physicists in Medicine.)- Published
- 2024
- Full Text
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24. Exploration of the pulse pileup effects in a clinical CdTe-based photon-counting computed tomography.
- Author
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Bhattarai M, Bache S, Abadi E, and Samei E
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- Tellurium, Tomography, X-Ray Computed methods, Phantoms, Imaging, Photons, Cadmium Compounds, Quantum Dots
- Abstract
Background: High tube current generates a high flux of x-rays to photon counting detectors (PCDs) that can potentially result in the piling up of pulses formed by concurrent photons, which can cause count loss and energy resolution degradation., Purpose: To evaluate the performance of clinical photon-counting CT (PCCT) systems in high flux, potentially influenced by pulse pileup effects, in terms of task-generic image quality metrics., Methods: A clinical phantom was scanned on a commercial PCCT scanner (NAEOTOM Alpha, Siemens) at 120 kV under fourteen different tube current levels (40-1000 mA) with a rotation time of 0.25 s and a pitch of 1. The dose levels corresponded to CTDI
vol (32 cm phantom) of 0.79-19.8 mGy. CT sinograms were reconstructed using QIR-off mode (noniterative reconstruction algorithm), Br44 kernel, and a voxel size of 0.4102 × 0.4102 × 3 mm 3 $0.4102 \times 0.4102 \times 3{\mathrm{\ mm}}^3$ . imQuest, an open-source MATLAB-based software package was used to calculate noise power spectrum (NPS), task transfer function (TTF), contrast-to-noise ratio (CNR), and CT number according to AAPM Task Group 233 metrology., Results: The 50% cut-off frequency of TTF (f50 ) remained mostly constant across all higher tube currents for all inserts, namely polyethylene, bone, air, and acrylic. Using the lowest two data points (40 and 80 mA), the expected relationship between noise magnitude and tube current was determined to be noise ∝ $ \propto \ $ mA-0.47 . The measured noise magnitude were up to 11.1% higher than the expected value at the highest tube current. The average frequency of NPS (fav ) decreased from 0.32 to 0.29 mm-1 as tube current increased from 40 to 1000 mA. No considerable effects were observed in CT number measurement of any insert; however, CT numbers for air and bone changed almost monotonically as tube current increased. Absolute CNR increased monotonically for all inserts; however, the difference between measured and expected CNRs were approximately -6% to 12% across all tube currents., Conclusions: Increasing tube currents did not affect the spatial resolution, but slightly affected the CT number and noise measurements of the clinical PCCT system. However, the effects were only considerable at clinically irrelevant tube currents used on a small 20-cm phantom. In general clinical practices, automatic exposure control techniques are used to decrease the variation of flux on the detector, which alleviates the chances of detector saturation due to high count rates. The observed effects could be due to pulse pileup, signal-dependent filtration of the system, or nonlinearities in the reconstruction algorithm. In conclusion, either the deadtime of the detector used in the photon-counting CT system is shorter such that count losses due to pulse pileup are negligible, or pulse pileup has inconsiderable effects on the image quality of clinical photon-counting CT systems in routine clinical practice due to possible corrections applied on the system., (© 2023 American Association of Physicists in Medicine.)- Published
- 2023
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25. Effect of controlled blood pressure increase on cerebral blood flow velocity and oxygenation in patients with subarachnoid haemorrhage.
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Olsen MH, Capion T, Riberholt CG, Bache S, Ebdrup SR, Rasmussen R, Mathiesen T, Berg RMG, and Møller K
- Subjects
- Humans, Blood Pressure, Cerebrovascular Circulation physiology, Oxygen metabolism, Intracranial Pressure, Ultrasonography, Doppler, Transcranial, Subarachnoid Hemorrhage complications, Brain Ischemia, Stroke
- Abstract
Background: Patients with aneurysmal subarachnoid haemorrhage (SAH) might have impaired cerebral autoregulation, that is, CBF - and thereby oxygen delivery - passively increase with an increase in CPP. This physiological study aimed to investigate the cerebral haemodynamic effects of controlled blood pressure increase in the early phase after SAH before any signs of delayed cerebral ischaemia (DCI) occurred., Methods: The study was carried out within 5 days after ictus. Data were recorded at baseline and after 20 min of noradrenaline infusion to increase mean arterial blood pressure (MAP) by a maximum of 30 mmHg and to an absolute level of no more than 130 mmHg. The primary outcome was the difference in middle cerebral artery blood flow velocity (MCAv) measured by transcranial Doppler (TCD), while differences in intracranial pressure (ICP), brain tissue oxygen tension (PbtO
2 ), and microdialysis markers of cerebral oxidative metabolism and cell injury were assessed as exploratory outcomes. Data were analysed using Wilcoxon signed-rank test with correction for multiplicity for the exploratory outcomes using the Benjamini-Hochberg correction., Results: Thirty-six participants underwent the intervention 4 (median, IQR: 3-4.75) days after ictus. MAP was increased from 82 (IQR: 76-85) to 95 (IQR: 88-98) mmHg (p-value: <.001). MCAv remained stable (baseline, median 57, IQR: 46-70 cm/s; controlled blood pressure increase, median: 55, IQR: 48-71 cm/s; p-value: .054), whereas PbtO2 increased significantly (baseline, median: 24, 95%CI: 19-31 mmHg; controlled blood pressure increase, median: 27, 95%CI: 24-33 mmHg; p-value <.001). The remaining exploratory outcomes were unchanged., Conclusion: In this study of patients with SAH, MCAv was not significantly affected by a brief course of controlled blood pressure increase; despite this, PbtO2 increased. This suggests that autoregulation might not be impaired in these patients or other mechanisms could mediate the increase in brain oxygenation. Alternatively, a CBF increase did occur that, in turn, increased cerebral oxygenation, but was not detected by TCD., Trial Registration: clinicaltrials.gov (NCT03987139; 14 June 2019)., (© 2023 The Authors. Acta Anaesthesiologica Scandinavica published by John Wiley & Sons Ltd on behalf of Acta Anaesthesiologica Scandinavica Foundation.)- Published
- 2023
- Full Text
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26. Quantitative performance of photon-counting CT at low dose: Virtual monochromatic imaging and iodine quantification.
- Author
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Vrbaski S, Bache S, Rajagopal J, and Samei E
- Subjects
- Humans, Tomography, X-Ray Computed methods, Tomography Scanners, X-Ray Computed, Phantoms, Imaging, Photons, Iodine
- Abstract
Background: Quantitative imaging techniques, such as virtual monochromatic imaging (VMI) and iodine quantification (IQ), have proven valuable diagnostic methods in several specific clinical tasks such as tumor and tissue differentiation. Recently, a new generation of computed tomography (CT) scanners equipped with photon-counting detectors (PCD) has reached clinical status., Purpose: This work aimed to investigate the performance of a new photon-counting CT (PC-CT) in low-dose quantitative imaging tasks, comparing it to an earlier generation CT scanner with an energy-integrating detector dual-energy CT (DE-CT). The accuracy and precision of the quantification across size, dose, material types (including low and high iodine concentrations), displacement from iso-center, and solvent (tissue background) composition were explored., Methods: Quantitative analysis was performed on two clinical scanners, Siemens SOMATOM Force and NAEOTOM Alpha using a multi-energy phantom with plastic inserts mimicking different iodine concentrations and tissue types. The tube configurations in the dual-energy scanner were 80/150Sn kVp and 100/150Sn kVp, while for PC-CT both tube voltages were set to either 120 or 140 kVp with photon-counting energy thresholds set at 20/65 or 20/70 keV. The statistical significance of patient-related parameters in quantitative measurements was examined using ANOVA and pairwise comparison with the posthoc Tukey honest significance test. Scanner bias was assessed in both quantitative tasks for relevant patient-specific parameters., Results: The accuracy of IQ and VMI in the PC-CT was comparable between standard and low radiation doses (p < 0.01). The patient size and tissue type significantly affect the accuracy of both quantitative imaging tasks in both scanners. The PC-CT scanner outperforms the DE-CT scanner in the IQ task in all cases. Iodine quantification bias in the PC-CT (-0.9 ± 0.15 mg/mL) at low doses in our study was comparable to that of DE-CT (range -2.6 to 1.5 mg/mL, published elsewhere) at a 1.7× higher dose, but the dose reduction severely biased DE-CT (4.72 ± 0.22 mg/mL). The accuracy in Hounsfield units (HU) estimation was comparable for 70 and 100 keV virtual imaging between scanners, but PC-CT was significantly underestimating virtual 40 keV HU values of dense materials in the phantom representing the extremely obese population., Conclusions: The statistical analysis of our measurements reveals better IQ at lower radiation doses using new PC-CT. Although VMI performance was mostly comparable between the scanners, the DE-CT scanner quantitatively outperformed PC-CT when estimating HU values in the specific case of very large phantoms and dense materials, benefiting from increased X-ray tube potentials., (© 2023 The Authors. Medical Physics published by Wiley Periodicals LLC on behalf of American Association of Physicists in Medicine.)
- Published
- 2023
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27. Pediatric Applications of Photon-Counting Detector CT.
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Cao J, Bache S, Schwartz FR, and Frush D
- Subjects
- Humans, Child, Phantoms, Imaging, Tomography, X-Ray Computed, Pediatrics instrumentation, Pediatrics methods, Radiology instrumentation, Radiology methods
- Abstract
Photon-counting detector (PCD) CT represents the most recent generational advance in CT technology. PCD CT has the potential to reduce image noise, improve spatial resolution and contrast resolution, and provide multispectral capability, all of which may be achieved with an overall decrease in the radiation dose. These effects may be used to reduce the iodinated contrast media dose and potentially obtain multiphase images through a single-acquisition technique. The benefits of PCD CT have previously been shown primarily in phantoms and adult patients. This article describes the application of PCD CT in children, as illustrated by clinical examples from a commercially available PCD CT system.
- Published
- 2023
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28. Reliability of cerebral autoregulation using different measures of perfusion pressure in patients with subarachnoid hemorrhage.
- Author
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Olsen MH, Capion T, Riberholt CG, Bache S, Berg RMG, and Møller K
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- Homeostasis physiology, Humans, Intracranial Pressure physiology, Perfusion, Reproducibility of Results, Subarachnoid Hemorrhage diagnostic imaging
- Abstract
Dynamic cerebral autoregulation to spontaneous fluctuations in cerebral perfusion pressure (CPP) is often assessed by transcranial Doppler (TCD) in the time domain, yielding primarily the mean flow index (Mx), or in the frequency domain using transfer function analysis (TFA), yielding gain and phase. For both domains, the measurement of blood pressure is critical. This study assessed the inter-method reliability of dynamic cerebral autoregulation using three different methods of pressure measurement. In 39 patients with aneurysmal subarachnoid hemorrhage, non-invasive arterial blood pressure (ABP), invasive ABP (measured in the radial artery) and CPP were recorded simultaneously with TCD. Intraclass correlation coefficient (ICC) was used to quantify reliability. Mx was higher when calculated using invasive ABP (0.39; 95% confidence interval [95% CI]: 0.33; 0.44) compared to non-invasive ABP, and CPP. The overall ICC showed poor to good reliability (0.65; 95% CI: 0.11; 0.84; n = 69). In the low frequency domain, the comparison between invasively measured ABP and CPP showed good to excellent (normalized gain, ICC: 0.87, 95CI: 0.81; 0.91; n = 96; non-normalized gain: 0.89, 95% CI: 0.84; 0.92; n = 96) and moderate to good reliability (phase, ICC: 0.69, 95% CI: 0.55; 0.79; n = 96), respectively. Different methods for pressure measurement in the assessment of dynamic cerebral autoregulation yield different results and cannot be used interchangeably., (© 2022 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)
- Published
- 2022
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29. Modulating physicochemical properties of tetrahydropyridine-2-amine BACE1 inhibitors with electron-withdrawing groups: A systematic study.
- Author
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Rombouts FJR, Hsiao CC, Bache S, De Cleyn M, Heckmann P, Leenaerts J, Martinéz-Lamenca C, Van Brandt S, Peschiulli A, Vos A, and Gijsen HJM
- Subjects
- Amidines chemistry, Amidines pharmacology, Amyloid Precursor Protein Secretases metabolism, Animals, Aspartic Acid Endopeptidases metabolism, Chemistry, Physical, Dogs, Dose-Response Relationship, Drug, Enzyme Inhibitors chemical synthesis, Enzyme Inhibitors chemistry, Humans, Molecular Structure, Pyrrolidines chemical synthesis, Pyrrolidines chemistry, Structure-Activity Relationship, Amyloid Precursor Protein Secretases antagonists & inhibitors, Aspartic Acid Endopeptidases antagonists & inhibitors, Electrons, Enzyme Inhibitors pharmacology, Pyrrolidines pharmacology
- Abstract
A common challenge for medicinal chemists is to reduce the pK
a of strongly basic groups' conjugate acids into a range that preserves the desired effects, usually potency and/or solubility, but avoids undesired effects like high volume of distribution (Vd ), limited membrane permeation, and off-target binding to, notably, the hERG channel and monoamine receptors. We faced this challenge with a 3,4,5,6-tetrahydropyridine-2-amine scaffold harboring an amidine, a key structural component of potential inhibitors of BACE1, the rate-limiting enzyme in the production of Aβ species that make up amyloid plaques in Alzheimer's disease. In our endeavor to balance potency with desirable properties to achieve brain penetration, we introduced a diverse set of groups in beta position of the amidine that modulate logD, PSA and pKa . Given the synthetic challenge to prepare these highly functionalized warheads, we first developed a design flow including predicted physicochemical parameters which allowed us to select only the most promising candidates for synthesis. For this we evaluated a set of commercial packages to predict physicochemical properties, which can guide medicinal chemists in their endeavors to modulate pKa values of amidine and amine bases., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)- Published
- 2022
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30. Early Brain Injury and Soluble ST2 After Nontraumatic Subarachnoid Hemorrhage.
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Schleicher RL, Bevers MB, Rubin DB, Koch MJ, Bache S, Lissak IA, Patel AB, Rosenthal ES, Møller K, and Kimberly WT
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- Biomarkers blood, Brain Injuries diagnostic imaging, Cohort Studies, Humans, Retrospective Studies, Subarachnoid Hemorrhage diagnostic imaging, Brain Injuries blood, Interleukin-1 Receptor-Like 1 Protein blood, Subarachnoid Hemorrhage blood
- Abstract
[Figure: see text].
- Published
- 2021
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31. Training non-intensivist doctors to work with COVID-19 patients in intensive care units.
- Author
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Engberg M, Bonde J, Sigurdsson ST, Møller K, Nayahangan LJ, Berntsen M, Eschen CT, Haase N, Bache S, Konge L, and Russell L
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- Adult, Clinical Competence, Female, Health Knowledge, Attitudes, Practice, Humans, Intensive Care Units, Male, Middle Aged, COVID-19 therapy, Critical Care, Physicians, SARS-CoV-2
- Abstract
Background: Due to an expected surge of COVID-19 patients in need of mechanical ventilation, the intensive care capacity was doubled at Rigshospitalet, Copenhagen, in March 2020. This resulted in an urgent need for doctors with competence in working with critically ill COVID-19 patients. A training course and a theoretical test for non-intensivist doctors were developed. The aims of this study were to gather validity evidence for the theoretical test and explore the effects of the course., Methods: The 1-day course was comprised of theoretical sessions and hands-on training in ventilator use, hemodynamic monitoring, vascular access, and use of personal protective equipment. Validity evidence was gathered for the test by comparing answers from novices and experts in intensive care. Doctors who participated in the course completed the test before (pretest), after (posttest), and again within 8 weeks following the course (retention test)., Results: Fifty-four non-intensivist doctors from 15 different specialties with a wide range in clinical experience level completed the course. The test consisted of 23 questions and demonstrated a credible pass-fail standard at 16 points. Mean pretest score was 11.9 (SD 3.0), mean posttest score 20.6 (1.8), and mean retention test score 17.4 (2.2). All doctors passed the posttest., Conclusion: Non-intensivist doctors, irrespective of experience level, can acquire relevant knowledge for working in the ICU through a focused 1-day evidence-based course. This knowledge was largely retained as shown by a multiple-choice test supported by validity evidence. The test is available in appendix and online., (© 2021 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)
- Published
- 2021
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32. Elevated miR-9 in Cerebrospinal Fluid Is Associated with Poor Functional Outcome After Subarachnoid Hemorrhage.
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Bache S, Rasmussen R, Wolcott Z, Rossing M, Møgelvang R, Tolnai D, Hassager C, Forman JL, Køber L, Nielsen FC, Kimberly WT, and Møller K
- Subjects
- Adult, Aged, Cohort Studies, Female, Humans, Male, Middle Aged, Prognosis, Biomarkers cerebrospinal fluid, MicroRNAs cerebrospinal fluid, Recovery of Function, Subarachnoid Hemorrhage cerebrospinal fluid
- Abstract
This study evaluated microRNA (miRNA) changes in cerebrospinal fluid (CSF) and their association with the occurrence of delayed cerebral ischemia (DCI) and poor functional outcome after SAH. Forty-three selected miRNAs were measured in daily CSF samples from a discovery cohort of SAH patients admitted to Rigshospitalet, Copenhagen, Denmark, and compared with neurologically healthy patients. Findings were validated in CSF from a replication cohort of SAH patients admitted to Massachusetts General Hospital, Boston, Massachusetts. The CSF levels of miRNA over time were compared with the occurrence of DCI, and functional outcome after 3 months. miRNAs were quantified in 427 CSF samples from 63 SAH patients in the discovery cohort, in 104 CSF samples from 63 SAH patients in the replication cohort, and in 11 CSF samples from 11 neurologically healthy patients. The miRNA profile changed remarkably immediately after SAH. Elevated miR-9-3p was associated with a poor functional outcome in the discovery cohort (p < 0.0001) after correction for multiple testing (q < 0.01) and in the replication cohort (p < 0.01). Furthermore, elevated miR-9-5p was associated with a poor functional outcome in the discovery cohort (p < 0.01) after correction for multiple testing (q < 0.05). No miRNA was associated with DCI in both cohorts. miR-9-3p and miR-9-5p are elevated in the CSF following SAH and this elevation is associated with a poor functional outcome. These elevations have potential roles in the progression of cerebral injury and could add to early prognostication.
- Published
- 2020
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33. Lectin complement pathway initiators after subarachnoid hemorrhage - an observational study.
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Matzen JS, Krogh CL, Forman JL, Garred P, Møller K, and Bache S
- Subjects
- Aged, Biomarkers blood, Biomarkers cerebrospinal fluid, Female, Follow-Up Studies, Humans, Longitudinal Studies, Male, Middle Aged, Prospective Studies, Retrospective Studies, Subarachnoid Hemorrhage diagnosis, Complement Pathway, Mannose-Binding Lectin physiology, Subarachnoid Hemorrhage blood, Subarachnoid Hemorrhage cerebrospinal fluid
- Abstract
Background: This exploratory study investigated the time-course of lectin complement pathway (LCP) initiators in cerebrospinal fluid (CSF) and plasma in patients with subarachnoid hemorrhage (SAH), as well as their relationship to delayed cerebral ischemia (DCI) and functional outcome., Methods: Concentrations of ficolin-1, ficolin-2, ficolin-3, and mannose-binding lectin (MBL) were analyzed in CSF and plasma from patients with SAH. Samples were collected daily from admission until day 9 (CSF; N_
PATIENTS = 63, n_SAMPLES = 399) and day 8 (plasma; N_PATIENTS = 50, n_SAMPLES = 358), respectively. Twelve neurologically healthy patients undergoing spinal anesthesia and 12 healthy blood donors served as controls. The development of DCI during hospitalization and functional outcome at 3 months (modified Rankin Scale) were registered for patients., Results: On admission, CSF levels of all LCP initiators were increased in SAH patients compared with healthy controls. Levels declined gradually over days in patients; however, a biphasic course was observed for ficolin-1. Increased CSF levels of all LCP initiators were associated with a poor functional outcome in univariate analyses. This relationship persisted for ficolin-1 and MBL in multivariate analysis after adjustments for confounders (age, sex, clinical severity, distribution and amount of blood on CT-imaging) and multiple testing (1.87 ng/mL higher in average, 95% CI, 1.17 to 2.99 and 1.69 ng/mL higher in average, 95% CI, 1.09 to 2.63, respectively). In patients who developed DCI compared with those without DCI, CSF levels of ficolin-1 and MBL tended to increase slightly more over time (p_interaction = 0.021 and 0.033, respectively); however, no association was found after adjustments for confounders and multiple testing (p-adj_interaction = 0.086 and 0.098, respectively). Plasma ficolin-1 and ficolin-3 were lower in SAH patients compared with healthy controls on all days. DCI and functional outcome were not associated with LCP initiator levels in plasma., Conclusion: Patients with SAH displayed elevated CSF levels of ficolin-1, ficolin-2, ficolin-3, and MBL. Increased CSF levels of ficolin-1 and MBL were associated with a poor functional outcome., Trial Registration: This study was a retrospective analysis of samples, which had been prospectively sampled and stored in a biobank. Registered at clinicaltrials.gov ( NCT01791257 , February 13, 2013, and NCT02320539 , December 19, 2014).- Published
- 2020
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34. Hypozincaemia is associated with severity of aneurysmal subarachnoid haemorrhage: a retrospective cohort study.
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Arleth T, Olsen MH, Orre M, Rasmussen R, Bache S, Eskesen V, Frikke-Schmidt R, and Møller K
- Subjects
- Adult, Aged, Brain Ischemia epidemiology, Female, Humans, Male, Middle Aged, Subarachnoid Hemorrhage complications, Subarachnoid Hemorrhage pathology, Brain Ischemia blood, Subarachnoid Hemorrhage blood, Zinc blood
- Abstract
Background: Hypozincaemia may develop in critically ill patients, including those with acute brain injury in the early phase after hospital admission. The aim of this study was to investigate the prevalence of hypozincaemia after aneurysmal subarachnoid haemorrhage (aSAH) and its association with delayed cerebral ischemia and functional outcome., Methods: We retrospectively analysed a cohort of 384 patients with SAH admitted to the Neurointensive Care Unit at Rigshospitalet, Copenhagen, Denmark, in whom at least one measurement of plasma zinc concentration was done during the hospital stay. Hypozincaemia was defined as at least one measurement of plasma zinc below 10 μmol/L. Potential associations between hypozincaemia, demographic variables and functional outcome after aSAH were analysed in multivariable logistic regression models., Results: Hypozincaemia was observed in 67% (n = 257) of all patients and occurred within 7 days in more than 95% of all hypozincaemic patients. In a multivariable model, severe SAH (WFNS 3-5; OR 4.2, CI 2.21-8.32, p < 0.001) and Sequential Organ Failure Assessment (SOFA) score on the day of admission (OR 1.24, CI 1.11-1.40, p < 0.001) were independently associated with hypozincaemia. In another multivariable model, hypozincaemia was independently associated with an unfavourable outcome (defined as a modified Rankin Scale score from 3 to 6) (OR 1.97, CI 1.06-3.68, p = 0.032), as was age (OR 1.03, CI 1.01-1.05, p = 0.015), SOFA score on the day of admission (OR 1.14, CI 1.02-1.29, p = 0.02), a diagnosis of delayed cerebral ischaemia (OR 4.06, CI 2.29-7.31, p < 0.001) and a clinical state precluding assessment for delayed cerebral ischaemia (OR 15.13, CI 6.59-38.03, p < 0.001)., Conclusion: Hypozincaemia occurs frequently after aSAH, is associated with a higher disease severity and independently contributes to an unfavourable outcome.
- Published
- 2020
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35. Free Flap Selection and Outcomes of Soft Tissue Reconstruction Following Resection of Intra-oral Malignancy.
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Young AMH, Bache S, Segaren N, Murphy S, Maraka J, and Durrani AJ
- Abstract
Introduction: Surgery to resect intra-oral malignancy is a well-established mode of primary treatment. The tissue requirement in this area is for a thin, pliable flap with minimal bulk and this has historically been provided by free tissue transfer with a radial forearm free flap (RFFF). More recently, a role for the anterolateral thigh free flap (ALTFF) has been described, although in populations with a westernized diet, body habitus may preclude use of an ALTFF due to flap thickness, relative to a radial forearm free flap. Methods: An analysis of data was performed retrospectively for 90 consecutive patients with intra-oral malignancy, requiring immediate soft tissue reconstruction by the senior author, at Addenbrooke's Hospital between July 2008 and April 2016. Cases requiring bony reconstruction were excluded. Data on patient age, sex, indication for surgery, tumor location and defect type, complications, success rates, and length of stay were recorded. Results: The majority of patients received an ALTFF ( n = 56) with 38% receiving a RFFF ( n = 34). Surgical resection took place in the floor of the mouth most frequently. These were closed with ALTFF and RFFF in 41 and 28 occasions, respectively. A success rate of 97% was observed in the RFFF group; 1 flap developed partial necrosis and required complete revision. In the ALTFF group, there was a 100% flap success rate. ALTFF usage resulted in a reduction in the number of intraoperative ( p = 0.021) in addition a reduction in the number of days in ITU ( p = 0.01) and post-operative clinic visits ( p = 0.025). Conclusion: We present a series that used predominately the ALTFF to reconstruct intra-oral defects following resection of squamous cell carcinoma in a Western population. The results demonstrate that this treatment can produce at least as comparable results as to the use of a RFFF repair in this population, whilst avoiding the donor site morbidity and aesthetic compromise of a RFFF., (Copyright © 2019 Young, Bache, Segaren, Murphy, Maraka and Durrani.)
- Published
- 2019
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36. Delayed cerebral ischaemia in patients with aneurysmal subarachnoid haemorrhage: Functional outcome and long-term mortality.
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Olsen MH, Orre M, Leisner ACW, Rasmussen R, Bache S, Welling KL, Eskesen V, and Møller K
- Subjects
- APACHE, Adolescent, Adult, Aged, Aged, 80 and over, Brain Ischemia therapy, Child, Consciousness Disorders etiology, Consciousness Disorders mortality, Female, Glasgow Coma Scale, Humans, Incidence, Kaplan-Meier Estimate, Male, Middle Aged, Nervous System Diseases etiology, Nervous System Diseases mortality, Retrospective Studies, Subarachnoid Hemorrhage therapy, Survival Analysis, Treatment Outcome, Young Adult, Brain Ischemia etiology, Brain Ischemia mortality, Subarachnoid Hemorrhage complications, Subarachnoid Hemorrhage mortality
- Abstract
Introduction: Delayed cerebral ischaemia (DCI) is one of the most frequent complications of aneurysmal subarachnoid haemorrhage (aSAH). The purpose of the present retrospective cohort study of patients with aSAH was to identify the association between DCI, functional outcome and 4-year mortality., Methods: Patients admitted to the Neurointensive Care Unit at Rigshospitalet, Copenhagen, with aSAH from 1 January 2010, through 31 December 2013 were registered. Patients were categorized into 3 groups: (a) those with DCI, defined as either a decline in consciousness or focal neurological deficits lasting ≥1 hour without any other detectable cause, (b) those without DCI, or (c) those who were unassessable for DCI. Functional neurological outcome after 6 months, as measured by the modified Rankin Scale (mRS), was dichotomized into good (mRS 0-2) and poor (mRS 3-6). Kaplan-Meier survival curves were constructed, and incidence risk rates were calculated both to determine the association between DCI and mortality., Results: Four hundred ninety-two cases of aSAH were recorded in the study period. DCI occurred in 23% of all patients, corresponding to 33% of assessable patients. Patients without DCI had the best functional outcome (mRS) compared to patients with DCI and patients who were unassessable; furthermore, the latter had worse outcomes than patients with DCI. Patients diagnosed with DCI had significantly higher mortality than those without DCI, even ignoring the first 14 days after admission., Conclusion: DCI may be associated with both short- and long-term morbidity and mortality in patients with aSAH., (© 2019 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.)
- Published
- 2019
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37. Soluble ST2 links inflammation to outcome after subarachnoid hemorrhage.
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Bevers MB, Wolcott Z, Bache S, Hansen C, Sastre C, Mylvaganam R, Koch MJ, Patel AB, Møller K, and Kimberly WT
- Subjects
- Case-Control Studies, Cerebrospinal Fluid metabolism, Cross-Sectional Studies, Female, Genetic Predisposition to Disease genetics, Humans, Inflammation complications, Inflammation Mediators metabolism, Interleukin-1 Receptor-Like 1 Protein blood, Interleukin-1 Receptor-Like 1 Protein genetics, Lipopolysaccharide Receptors biosynthesis, Longitudinal Studies, Male, Middle Aged, Monocytes metabolism, Outcome Assessment, Health Care, Receptors, IgG biosynthesis, Subarachnoid Hemorrhage complications, Inflammation genetics, Interleukin-1 Receptor-Like 1 Protein metabolism, Subarachnoid Hemorrhage genetics
- Abstract
Objective: To investigate whether soluble growth stimulation expressed gene 2 (sST2), a prognostic marker in cardiovascular and inflammatory disorders, is associated with neurological injury after aneurysmal subarachnoid hemorrhage (SAH)., Methods: We studied SAH patients from 2 independent cohorts. Outcome assessments included functional status at 90 days using the modified Rankin Scale (mRS), mortality, and delayed cerebral ischemia (DCI). The relationships between sST2 plasma level and outcome measures were assessed in both cross-sectional and longitudinal analysis. Primary blood mononuclear cells from SAH patients and elective aneurysm controls were analyzed by multiparameter flow cytometry., Results: In the discovery cohort, sST2 predicted 90-day mRS 3-6 (C index = 0.724, p < 0.001) and mortality in Kaplan-Meier analysis (p < 0.001). The association with functional status was independent of age, sex, World Federation of Neurosurgical Societies score, modified Fisher score, treatment modality, and cardiac comorbidities (adjusted odds ratio = 2.28, 95% confidence interval = 1.04-5.00, p = 0.039). Higher sST2 concentration was observed in those patients with DCI (90.8 vs 53.7ng/ml, p = 0.003). These associations were confirmed in a replication cohort. In patients with high sST2, flow cytometry identified decreased expression of CD14 (4.27 × 10
5 ± 2,950 arbitrary unit (AU) vs 5.64 × 105 ± 1,290 AU, p < 0.001), and increased expression of CD16 (39,960 ± 272 AU vs 34,869 ± 183 AU, p < 0.001)., Interpretation: Plasma sST2 predicts DCI, functional outcome, and mortality after SAH, independent of clinical and radiographic markers. Elevated sST2 is also associated with changes in CD14+ CD16+ monocytes. ANN NEUROL 2019;86:384-394., (© 2019 American Neurological Association.)- Published
- 2019
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38. Plasma Levels of IL-6, IL-8, IL-10, ICAM-1, VCAM-1, IFNγ, and TNFα are not Associated with Delayed Cerebral Ischemia, Cerebral Vasospasm, or Clinical Outcome in Patients with Subarachnoid Hemorrhage.
- Author
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Rasmussen R, Bache S, Stavngaard T, and Møller K
- Subjects
- Adult, Aged, Biomarkers blood, Brain Ischemia etiology, Female, Humans, Inflammation blood, Inflammation immunology, Male, Middle Aged, Observational Studies as Topic, Subarachnoid Hemorrhage immunology, Subarachnoid Hemorrhage therapy, Treatment Outcome, Vasospasm, Intracranial etiology, Young Adult, Brain Ischemia blood, Brain Ischemia immunology, Subarachnoid Hemorrhage blood, Subarachnoid Hemorrhage complications, Vasospasm, Intracranial blood, Vasospasm, Intracranial immunology
- Abstract
Background: Delayed cerebral ischemia (DCI) is a serious and frequent complication following subarachnoid hemorrhage (SAH). The pathophysiology behind DCI remains poorly understood, but inflammation has been proposed to play a significant role. This study investigated the relationship between plasma levels of some of the most important inflammatory markers and DCI, cerebral vasospasm, and functional outcome in patients with SAH., Methods: In 90 patients with SAH, interleukin-6, intercellular adhesion molecule-1, vascular cell adhesion molecule-1, high sensitivity C-reactive protein (HsCRP), interleukin-8, interleukin-10, interferon gamma, and tumor necrosis factor alpha were measured in peripheral blood day 3 and day 8 after SAH. Any occurrence of DCI or infection was recorded, and computed tomography angiography was performed on day 8. Clinical outcome was assessed after 3 months., Results: HsCRP on day 3 was higher in patients with angiographic vasospasm (P = 0.003), and HsCRP on day 8 was higher in patients with poor outcome (P = 0.014). No association with DCI, vasospasm, or outcome was found for any of the remaining analyzed substances., Conclusions: High plasma levels of HsCRP were significantly associated with angiographic vasospasm and clinical outcome. Plasma levels of interleukin-6, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, interleukin-8, interleukin-10, interferon gamma, and tumor necrosis factor alpha were not associated with DCI, angiographic vasospasm, or clinical outcome at 3 months., (Copyright © 2019 Elsevier Inc. All rights reserved.)
- Published
- 2019
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39. [Aneurysmal subarachnoid haemorrhage].
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Olsen MH, Lilja-Cyron A, Bache S, Eskesen V, and Møller K
- Subjects
- Humans, Intracranial Aneurysm diagnosis, Intracranial Aneurysm therapy, Subarachnoid Hemorrhage diagnosis, Subarachnoid Hemorrhage therapy
- Abstract
The purpose of this review is to increase the knowledge about diagnosis and treatment of aneurysmal subarachnoid haemorrhage (aSAH), which is an infrequent and critical condition with a high risk of severe morbidity and mortality. The outcome is improved by correct and efficient diagnosis and early treatment, including aneurysm repair. General practitioners and doctors in the departments for emergency medicine should be aware of the symptoms of aSAH.
- Published
- 2019
40. Implementation of a checklist to enhance operation note quality at a UK burns centre.
- Author
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Khajuria A, Charles W, Williams A, Leon-Villapalos J, Atkins J, Jones I, Bache S, and Collins D
- Subjects
- Guideline Adherence, Humans, Quality Improvement, United Kingdom, Venous Thromboembolism prevention & control, Burns surgery, Checklist, Documentation standards
- Abstract
Introduction: Operation notes are fundamental for clinical, academic and medico-legal purposes. Good Surgical Practice (2014) provides guidelines to assist note completion but the literature suggests poor adherence to these. The aim of this study was to evaluate and improve operation note quality at a UK burns centre through implementation of a burns surgery-specific checklist., Methods: A 22-component burns surgery-specific checklist, modified from Good Surgical Practice (2014), was designed and implemented. The quality of 80 operation notes (40 pre and 40 post-implementation) was assessed against this checklist. Fisher's exact and Mann-Whitney U statistical tests were used to evaluate pre and post-intervention note quality., Results: Before checklist implementation, only 6/22 components (27.3%) were recorded on every note. 4/22 components (18.2%) were not recorded on any, including microbiology specimen and clinical photography, which are particularly important in burns. After implementation, 16/22 (72.7%) were recorded on every note, with a statistically significant improvement in all other components (p≤0.01), except venous thromboembolism prophylaxis (p=0.10). The median percentage score of components recorded improved from 78.2 to 100% (p<0.01)., Conclusion: To our knowledge, this is the first study in available literature to show that a burns surgery-specific checklist can significantly improve burns operation note quality. This presents a simple and cheap method to improve note quality and may enhance post-operative intra/inter-team communication and patient care. At our unit, we have now developed an electronic checklist format with mandatory field completion to facilitate total compliance., (Copyright © 2018 Elsevier Ltd and ISBI. All rights reserved.)
- Published
- 2019
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41. Effect of tube current on computed tomography radiomic features.
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Mackin D, Ger R, Dodge C, Fave X, Chi PC, Zhang L, Yang J, Bache S, Dodge C, Jones AK, and Court L
- Subjects
- Carcinoma, Non-Small-Cell Lung pathology, Humans, Phantoms, Imaging, Electricity, Image Processing, Computer-Assisted methods, Tomography, X-Ray Computed methods, Tomography, X-Ray Computed standards
- Abstract
Variability in the x-ray tube current used in computed tomography may affect quantitative features extracted from the images. To investigate these effects, we scanned the Credence Cartridge Radiomics phantom 12 times, varying the tube current from 25 to 300 mA∙s while keeping the other acquisition parameters constant. For each of the scans, we extracted 48 radiomic features from the categories of intensity histogram (n = 10), gray-level run length matrix (n = 11), gray-level co-occurrence matrix (n = 22), and neighborhood gray tone difference matrix (n = 5). To gauge the size of the tube current effects, we scaled the features by the coefficient of variation of the corresponding features extracted from images of non-small cell lung cancer tumors. Variations in the tube current had more effect on features extracted from homogeneous materials (acrylic, sycamore wood) than from materials with more tissue-like textures (cork, rubber particles). Thirty-eight of the 48 features extracted from acrylic were affected by current reductions compared with only 2 of the 48 features extracted from rubber particles. These results indicate that variable x-ray tube current is unlikely to have a large effect on radiomic features extracted from computed tomography images of textured objects such as tumors.
- Published
- 2018
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42. MicroRNA Changes in Cerebrospinal Fluid After Subarachnoid Hemorrhage.
- Author
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Bache S, Rasmussen R, Rossing M, Laigaard FP, Nielsen FC, and Møller K
- Subjects
- Adult, Aged, Brain Ischemia cerebrospinal fluid, Case-Control Studies, Female, High-Throughput Nucleotide Sequencing, Humans, Male, Middle Aged, Prospective Studies, Real-Time Polymerase Chain Reaction, Sequence Analysis, RNA, Subarachnoid Hemorrhage cerebrospinal fluid, Brain Ischemia genetics, MicroRNAs cerebrospinal fluid, Subarachnoid Hemorrhage genetics
- Abstract
Background and Purpose: Delayed cerebral ischemia (DCI) accounts for a major part of the morbidity and mortality after aneurysmal subarachnoid hemorrhage (SAH). MicroRNAs (miRNAs) are pathophysiologically involved in acute cerebral ischemia. This study compared miRNA profiles in cerebrospinal fluid from neurologically healthy patients, as well as SAH patients with and without subsequent development of DCI., Methods: In a prospective case-control study of SAH patients treated with external ventricular drainage and neurologically healthy patients, miRNA profiles in cerebrospinal fluid were screened and validated using 2 different high-throughput real-time quantification polymerase chain reaction techniques. The occurrence of DCI was documented in patient charts and subsequently reviewed independently by 2 physicians., Results: MiRNA profiles from 27 SAH patients and 10 neurologically healthy patients passed quality control. In the validation, 66 miRNAs showed a relative increase in cerebrospinal fluid from SAH patients compared with neurologically healthy patients ( P <0.001); 2 (miR-21 and miR-221) showed a relative increase in SAH patients with DCI compared with those without ( P <0.05) in both the screening and validation., Conclusions: SAH is associated with marked changes in the cerebrospinal fluid miRNA profile. These changes could be associated to the development of DCI., Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01791257., (© 2017 The Authors.)
- Published
- 2017
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43. The impact of major trauma network triage systems on patients with major burns.
- Author
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Nizamoglu M, O'Connor EF, Bache S, Theodorakopoulou E, Sen S, Sherren P, Barnes D, and Dziewulski P
- Subjects
- Adult, Aged, Aged, 80 and over, Body Surface Area, Burn Units, Burns mortality, Cooperative Behavior, Emergency Service, Hospital, Female, Humans, Male, Middle Aged, Resuscitation, Retrospective Studies, Survival Rate, Time-to-Treatment, Trauma Severity Indices, United Kingdom, Young Adult, Burns therapy, Patient Transfer statistics & numerical data, Trauma Centers organization & administration, Triage organization & administration
- Abstract
Introduction: Trauma is a leading cause of death and disability worldwide. Patients presenting with severe trauma and burns benefit from specifically trained multidisciplinary teams. Regional trauma systems have shown improved outcomes for trauma patients. The aim of this study is to determine whether the development of major trauma systems have improved the management of patients with major burns., Methods: A retrospective study was performed over a four-year period reviewing all major burns in adults and children received at a regional burns centre in the UK before and after the implementation of the regional trauma systems and major trauma centres (MTC). Comparisons were drawn between three areas: (1) Patients presenting before the introduction of MTC and after the introduction of MTC. (2) Patients referred from MTC and non-MTC within the region, following the introduction of MTC. (3) Patients referred using the urban trauma protocol and the rural trauma protocol., Results: Following the introduction of regional trauma systems and major trauma centres (MTC), isolated burn patients seen at our regional burns centre did not show any significant improvement in transfer times, admission resuscitation parameters, organ dysfunction or survival when referred from a MTC compared to a non-MTC emergency department. There was also no significant difference in survival when comparing referrals from all hospitals pre and post establishment of the major trauma network., Conclusion: No significant outcome benefit was demonstrated for burns patients referred via MTCs compared to non-MTCs. We suggest further research is needed to ascertain whether burns patients benefit from prolonged transfer times to a MTC compared to those seen at their local hospitals prior to transfer to a regional burns unit for further specialist care., (Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.)
- Published
- 2016
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44. Optical-CT 3D Dosimetry Using Fresnel Lenses with Minimal Refractive-Index Matching Fluid.
- Author
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Bache S, Malcolm J, Adamovics J, and Oldham M
- Subjects
- Artifacts, Dose-Response Relationship, Radiation, Gamma Rays, Radiometry, Solutions, Imaging, Three-Dimensional, Lenses, Refractometry, Tomography, X-Ray Computed
- Abstract
Telecentric optical computed tomography (optical-CT) is a state-of-the-art method for visualizing and quantifying 3-dimensional dose distributions in radiochromic dosimeters. In this work a prototype telecentric system (DFOS-Duke Fresnel Optical-CT Scanner) is evaluated which incorporates two substantial design changes: the use of Fresnel lenses (reducing lens costs from $10-30K t0 $1-3K) and the use of a 'solid tank' (which reduces noise, and the volume of refractively matched fluid from 1 ltr to 10 cc). The efficacy of DFOS was evaluated by direct comparison against commissioned scanners in our lab. Measured dose distributions from all systems were compared against the predicted dose distributions from a commissioned treatment planning system (TPS). Three treatment plans were investigated including a simple four-field box treatment, a multiple small field delivery, and a complex IMRT treatment. Dosimeters were imaged within 2 h post irradiation, using consistent scanning techniques (360 projections acquired at 1 degree intervals, reconstruction at 2mm). DFOS efficacy was evaluated through inspection of dose line-profiles, and 2D and 3D dose and gamma maps. DFOS/TPS gamma pass rates with 3%/3mm dose difference/distance-to-agreement criteria ranged from 89.3% to 92.2%, compared to from 95.6% to 99.0% obtained with the commissioned system. The 3D gamma pass rate between the commissioned system and DFOS was 98.2%. The typical noise rates in DFOS reconstructions were up to 3%, compared to under 2% for the commissioned system. In conclusion, while the introduction of a solid tank proved advantageous with regards to cost and convenience, further work is required to improve the image quality and dose reconstruction accuracy of the new DFOS optical-CT system.
- Published
- 2016
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45. Detection and quantification of microRNA in cerebral microdialysate.
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Bache S, Rasmussen R, Rossing M, Hammer NR, Juhler M, Friis-Hansen L, Nielsen FC, and Møller K
- Subjects
- Brain metabolism, Brain Injuries cerebrospinal fluid, Humans, Perfusion, RNA Processing, Post-Transcriptional, Reproducibility of Results, Temperature, Treatment Outcome, Cerebrospinal Fluid chemistry, MicroRNAs cerebrospinal fluid, Microdialysis methods, Subarachnoid Hemorrhage cerebrospinal fluid
- Abstract
Background: Secondary brain injury accounts for a major part of the morbidity and mortality in patients with spontaneous aneurysmal subarachnoid hemorrhage (SAH), but the pathogenesis and pathophysiology remain controversial. MicroRNAs (miRNAs) are important posttranscriptional regulators of complementary mRNA targets and have been implicated in the pathophysiology of other types of acute brain injury. Cerebral microdialysis is a promising tool to investigate these mechanisms. We hypothesized that miRNAs would be present in human cerebral microdialysate., Methods: RNA was extracted and miRNA profiles were established using high throughput real-time quantification PCR on the following material: 1) Microdialysate sampled in vitro from A) a solution of total RNA extracted from human brain, B) cerebrospinal fluid (CSF) from a neurologically healthy patient, and C) a patient with SAH; and 2) cerebral microdialysate and CSF sampled in vivo from two patients with SAH. MiRNAs were categorized according to their relative recovery (RR) and a pathway analysis was performed for miRNAs exhibiting a high RR in vivo., Results: Seventy-one of the 160 miRNAs detected in CSF were also found in in vivo microdialysate from SAH patients. Furthermore specific miRNAs consistently exhibited either a high or low RR in both in vitro and in vivo microdialysate. Analysis of repeatability showed lower analytical variation in microdialysate than in CSF., Conclusions: MiRNAs are detectable in cerebral microdialysate; a large group of miRNAs consistently showed a high RR in cerebral microdialysate. Measurement of cerebral interstitial miRNA concentrations may aid in the investigation of secondary brain injury in neurocritical conditions.
- Published
- 2015
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46. Real-time changes in brain tissue oxygen during endovascular treatment of cerebral vasospasm.
- Author
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Rasmussen R, Bache S, Stavngaard T, Skjøth-Rasmussen J, and Romner B
- Subjects
- Brain blood supply, Brain metabolism, Brain Ischemia etiology, Brain Ischemia metabolism, Cerebral Revascularization methods, Female, Humans, Male, Middle Aged, Partial Pressure, Time Factors, Treatment Outcome, Angioplasty, Balloon methods, Cerebrovascular Circulation physiology, Oxygen metabolism, Subarachnoid Hemorrhage complications, Subarachnoid Hemorrhage metabolism, Subarachnoid Hemorrhage therapy, Vasospasm, Intracranial etiology, Vasospasm, Intracranial metabolism
- Abstract
The use of endovascular intervention to treat cerebral vasospasm after subarachnoid hemorrhage has increased. Although the effect on angiographic vasospasm can be easily demonstrated, the effect on cerebral blood flow and clinical outcome is still controversial. In this report, we investigate minute-by-minute changes in brain tissue oxygen during balloon angioplasty and intraarterial administration of vasodilators in three patients.Our results confirm that endovascular intervention is capable of not only resolving angiographic vasospasm, but also of normalizing values of brain tissue oxygen pressure (PtiO₂) in target parenchyma. However, during the intervention, dangerously low levels of brain tissue oxygen, leading to cerebral infarction, may occur. Thus, no clinical improvement was seen in two of the patients and a dramatic worsening was observed in the third patient. Because the decrease in brain tissue oxygen was seen after administration of vasopressor agents, this may be a contributing factor.
- Published
- 2015
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47. Serotonin 2A receptor agonist binding in the human brain with [¹¹C]Cimbi-36.
- Author
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Ettrup A, da Cunha-Bang S, McMahon B, Lehel S, Dyssegaard A, Skibsted AW, Jørgensen LM, Hansen M, Baandrup AO, Bache S, Svarer C, Kristensen JL, Gillings N, Madsen J, and Knudsen GM
- Subjects
- Female, Humans, Male, Receptor, Serotonin, 5-HT2A metabolism, Young Adult, Benzylamines pharmacokinetics, Brain diagnostic imaging, Phenethylamines pharmacokinetics, Positron-Emission Tomography methods, Radiopharmaceuticals pharmacokinetics, Receptor, Serotonin, 5-HT2A analysis, Serotonin 5-HT2 Receptor Agonists pharmacokinetics
- Abstract
[(11)C]Cimbi-36 was recently developed as a selective serotonin 2A (5-HT(2A)) receptor agonist radioligand for positron emission tomography (PET) brain imaging. Such an agonist PET radioligand may provide a novel, and more functional, measure of the serotonergic system and agonist binding is more likely than antagonist binding to reflect 5-HT levels in vivo. Here, we show data from a first-in-human clinical trial with [(11)C]Cimbi-36. In 29 healthy volunteers, we found high brain uptake and distribution according to 5-HT(2A) receptors with [(11)C]Cimbi-36 PET. The two-tissue compartment model using arterial input measurements provided the most optimal quantification of cerebral [(11)C]Cimbi-36 binding. Reference tissue modeling was feasible as it induced a negative but predictable bias in [(11)C]Cimbi-36 PET outcome measures. In five subjects, pretreatment with the 5-HT(2A) receptor antagonist ketanserin before a second PET scan significantly decreased [(11)C]Cimbi-36 binding in all cortical regions with no effects in cerebellum. These results confirm that [(11)C]Cimbi-36 binding is selective for 5-HT(2A) receptors in the cerebral cortex and that cerebellum is an appropriate reference tissue for quantification of 5-HT(2A) receptors in the human brain. Thus, we here describe [(11)C]Cimbi-36 as the first agonist PET radioligand to successfully image and quantify 5-HT(2A) receptors in the human brain.
- Published
- 2014
- Full Text
- View/download PDF
48. [Indirect azygos vein continuation syndrome with segmental agenesis and saccular aneurysm of the inferior vena cava].
- Author
-
Bergmann K, Lemmer A, Artjuschenko T, and Bache St
- Subjects
- Adolescent, Aneurysm diagnosis, Angiography, Azygos Vein pathology, Blood Flow Velocity physiology, Female, Humans, Tomography, X-Ray Computed, Ultrasonography, Doppler, Urography, Vena Cava, Inferior pathology, Aneurysm congenital, Azygos Vein abnormalities, Diagnostic Imaging, Vena Cava, Inferior abnormalities
- Abstract
Indirect vena azygos continuation syndrome and aneurysm are rare variations of the inferior vena cava (IVC). In this article we describe the ultrasound, angiographic and CT appearance of a 14-year-old girl with this congenital anormaly of the IVC.
- Published
- 1995
49. [The general practitioner and public health authorities. I..].
- Author
-
BACHE S
- Subjects
- Humans, Family Practice, General Practice, General Practitioners, Group Processes, Public Health
- Published
- 1953
50. [Masked brain- and subphrenic abscesses during penicillin therapy].
- Author
-
BACHE S
- Subjects
- Humans, Brain, Penicillins pharmacology, Subphrenic Abscess
- Published
- 1951
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