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Bak-Misiuk J, Wolska A, Lawniczak-Jablonska K, Klepka M, Sadowski J, Holub-Krappe E, Persson A, Arvanitis D, Dynowska E, Romanowski P, Domagala J, Caliebe W. Structural and magnetic properties of MBE-grown MnSb layers. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308095263] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Holub-Krappe E, Andersson C, Sakamaki M, Konishi T, Fujikawa T, Rossner H, Sanyal B, Eriksson O, Nordstrom L, Hunter Dunn J, Persson A, Karis O, Arvanitis D. Structural effects and the spin reorientation in Au/Co/Au films. Acta Crystallogr A 2008. [DOI: 10.1107/s0108767308096852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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Persson A. Sero-silence and sero-sharing: managing HIV in serodiscordant heterosexual relationships. AIDS Care 2008; 20:503-6. [DOI: 10.1080/09540120701787487] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Mindus P, Ehrin E, Ericsson L, Farde L, Hedström C, Litton J, Persson A, Sedvall G. Central Benzodiazepine Receptor Binding Studied with 11-C Labelled Ro 15-1788 and Positron Emission Tomography. PHARMACOPSYCHIATRY 2008. [DOI: 10.1055/s-2007-1017137] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Hartford M, Wiklund O, Mattsson Hultén L, Persson A, Karlsson T, Herlitz J, Caidahl K. C-reactive protein, interleukin-6, secretory phospholipase A2 group IIA and intercellular adhesion molecule-1 in the prediction of late outcome events after acute coronary syndromes. J Intern Med 2007; 262:526-36. [PMID: 17908161 DOI: 10.1111/j.1365-2796.2007.01862.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE We investigated whether levels of C-reactive protein (CRP), interleukin-6 (IL-6), secretory phospholipase A(2) group IIA (sPLA(2)-IIA) and intercellular adhesion molecule-1 (ICAM-I) predict late outcomes in patients with acute coronary syndromes (ACS). DESIGN Prospective longitudinal study. CRP (mg L(-1)), IL-6 (pg mL(-1)), sPLA(2)-IIA (ng mL(-1)) and ICAM-1 (ng mL(-1)) were measured at days 1 (n = 757) and 4 (n = 533) after hospital admission for ACS. Their relations to mortality and rehospitalization for myocardial infarction (MI) and congestive heart failure (CHF) were determined. SETTING Coronary Care Unit at Sahlgrenska University Hospital, Gothenburg, Sweden. SUBJECTS Patients with ACS alive at day 30; median follow-up 75 months. RESULTS Survival was related to day 1 levels of all markers. After adjustment for confounders, CRP, IL-6 and ICAM-1, but not sPLA(2)-IIA, independently predicted mortality and rehospitalization for CHF. For CRP, the hazard ratio (HR) was 1.3 for mortality (95% confidence interval (CI): 1.1-1.5, P = 0.003) and 1.4 for CHF (95% CI: 1.1-1.9, P = 0.006). For IL-6, HR was 1.3 for mortality (95% CI: 1.1-1.6, P < 0.001) and 1.4 for CHF (95% CI: 1.1-1.8, P = 0.02). For ICAM-1, HR was 1.2 for mortality (95% CI: 1.0-1.4, P = 0.04) and 1.3 for CHF (95% CI: 1.0-1.7, P = 0.03). No marker predicted MI. Marker levels on day 4 provided no additional predictive value. CONCLUSIONS In patients with ACS, CRP, IL-6, sPLA(2)-IIA and ICAM-1 are associated with long-term mortality and CHF, but not reinfarction. CRP, IL-6 and ICAM-1 provide prognostic information beyond that obtained by clinical variables.
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Glanz C, Rebetz J, Stewénius Y, Persson A, Englund E, Mandahl N, Mertens F, Salford LG, Widegren B, Fan X, Gisselsson D. Genetic intratumour heterogeneity in high-grade brain tumours is associated with telomere-dependent mitotic instability. Neuropathol Appl Neurobiol 2007; 33:440-54. [PMID: 17617873 DOI: 10.1111/j.1365-2990.2007.00832.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Glioblastoma multiforme (GBM) and other high-grade brain tumours are typically characterized by complex chromosome abnormalities and extensive intratumour cytogenetic heterogeneity. The mechanisms behind this diversity have been little explored. In this study, we analysed the pattern of chromosome segregation at mitosis in 20 brain tumours. We found an abnormal segregation of chromatids at mitosis through anaphase bridging (10-25% of anaphase cells) in all 10 GBMs. Anaphase bridging was also found in two medulloblastomas (7-15%), one anaplastic astrocytoma (17%) and one oligodendroglioma (6%). These tumours showed a relatively high degree of cytogenetic complexity and heterogeneity. In contrast, cell division abnormalities were not found in low-grade brain tumours with less complex karyotypes, including two pilocytic astrocytomas and two ependymomas. Further analysis of two GBMs by fluorescence in situ hybridization with telomeric repeat probes revealed excessive shortening of TTAGGG repeats, indicating dysfunctional protection of chromosome ends. In xenografts established from these GBMs, there was a gradual reduction in cytogenetic heterogeneity through successive passages as the proportion of abnormally short telomeres was reduced and the frequency of anaphase bridges decreased from >25% to 0. However, bridging could be reintroduced in late-passage xenograft cells by pharmacological induction of telomere shortening, using a small-molecule telomerase inhibitor. Telomere-dependent abnormal segregation of chromosomes at mitosis is thus a common phenomenon in high-grade brain tumours and may be one important factor behind cytogenetic intratumour diversity in GBM.
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Lundh O, Lindau F, Persson A, Wahlström CG, McKenna P, Batani D. Influence of shock waves on laser-driven proton acceleration. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2007; 76:026404. [PMID: 17930159 DOI: 10.1103/physreve.76.026404] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2007] [Indexed: 05/25/2023]
Abstract
The influence of shock waves, driven by amplified spontaneous emission (ASE), on laser-accelerated proton beams is investigated. A local deformation, produced by a cold shock wave launched by the ablation pressure of the ASE pedestal, can under oblique laser irradiation significantly direct the proton beam toward the laser axis. This can be understood in the frame of target normal sheath acceleration as proton emission from an area of the target where the local target normal is shifted toward the laser axis. Hydrodynamic simulations and experimental data show that there exists a window in laser and target parameter space where the target can be significantly deformed and yet facilitate efficient proton acceleration. The dependence of the magnitude of the deflection on target material, foil thickness, and ASE pedestal intensity and duration is experimentally investigated. The deflection angle is found to increase with increasing ASE intensity and duration and decrease with increasing target thickness. In a comparison between aluminum and copper target foils, aluminum is found to yield a larger proton beam deflection. An analytic model is successfully used to predict the proton emission direction.
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Lindau F, Lundh O, Persson A, Cassou K, Kazamias S, Ros D, Plé F, Jamelot G, Klisnick A, de Rossi S, Joyeux D, Zielbauer B, Ursescu D, Kühl T, Wahlström CG. Quantitative study of 10 Hz operation of a soft x-ray laser-energy stability and target considerations. OPTICS EXPRESS 2007; 15:9486-9493. [PMID: 19547296 DOI: 10.1364/oe.15.009486] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
A soft x-ray laser from Ni-like Mo, pumped in grazing incidence (GRIP), is analyzed with regard to high repetition rate operation. Reliable lasing is obtained, but with significant energy fluctuations attributed mainly to beam pointing jitter from the pump laser. Two modes of operation are compared: continuously moving target and stationary target. With a moving target the soft X-ray output is constant on average, whereas the repeated use of the same target position leads to a pulse energy which increases for several tens of shots. This effect might be caused by improved guiding of the pump laser in the formed groove and the removal, through laser ablation, of the oxide layer on the target surface.
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Dahlström N, Persson A, Albiin N, Smedby O, Brismar TB. Contrast-enhanced magnetic resonance cholangiography with Gd-BOPTA and Gd-EOB-DTPA in healthy subjects. Acta Radiol 2007; 48:362-8. [PMID: 17453513 DOI: 10.1080/02841850701196922] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE To evaluate the biliary enhancement dynamics of the two gadolinium chelates Gd-BOPTA (MultiHance) and Gd-EOB-DTPA (Primovist) in normal healthy subjects. MATERIAL AND METHODS Ten healthy volunteers were evaluated with both agents by magnetic resonance (MR) imaging at 1.5T using a breath-hold gradient-echo T1-weighted VIBE sequence. The relative signal intensity (SI) differences between the common hepatic duct (CHD) and liver parenchyma were measured before and 10, 20, 30, 40, 130, 240, and 300 min after contrast medium injection. RESULTS Biliary enhancement was obvious 10 min post-injection for Gd-EOB-DTPA and was noted at 20 min for Gd-BOPTA. At 40 min delay, Gd-BOPTA reached its peak biliary enhancement, but at neither 30 nor 40 min delay was there any significant difference compared with that of Gd-EOB-DTPA. At later delays, the contrast between CHD and liver continued to increase for Gd-EOB-DTPA, whereas it decreased for Gd-BOPTA. CONCLUSION The earlier onset and longer duration of a high contrast between CHD and liver for Gd-EOB-DTPA facilitates examination of hepatobiliary excretion. Therefore, Gd-EOB-DTPA may provide adequate hepatobiliary imaging within a shorter time span than Gd-BOPTA and facilitate scheduling at the MR unit. Further studies in patients are required to compare the imaging advantages of Gd-EOB-DTPA and Gd-BOPTA in clinical practice.
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Cassou K, Kazamias S, Ros D, Plé F, Jamelot G, Klisnick A, Lundh O, Lindau F, Persson A, Wahlström CG, de Rossi S, Joyeux D, Zielbauer B, Ursescu D, Kühl T. Optimization toward a high-average-brightness soft-x-ray laser pumped at grazing incidence. OPTICS LETTERS 2007; 32:139-41. [PMID: 17186043 DOI: 10.1364/ol.32.000139] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
We report the near-field imaging characterization of a 10 Hz Ni-like 18.9 nm molybdenum soft-x-ray laser pumped in a grazing incidence pumping (GRIP) geometry with a table-top laser driver. We investigate the effect of varying the GRIP angle on the spatial behavior of the soft-x-ray laser source. After multiparameter optimization, we were able to find conditions to generate routinely a high-repetition-rate soft-x-ray laser with an energy level of up to 3 microJ/pulse and to 6x10(17) photons/s/mm2/mrad2/(0.1% bandwidth) average brightness and 1x10(28) photons/s/mm2/mrad2/(0.1% bandwidth) peak brightness.
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Nilsson PA, Lundberg P, Bronmark C, Persson A, Turesson H. Behavioral interference and facilitation in the foraging cycle shape the functional response. Behav Ecol 2006. [DOI: 10.1093/beheco/arl094] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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Persson A. Imaging technology of the future. Br J Surg 2006; 93:1182-4. [PMID: 16983739 DOI: 10.1002/bjs.5567] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Expectation of imaging-based treatments
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Mangles SPD, Thomas AGR, Kaluza MC, Lundh O, Lindau F, Persson A, Tsung FS, Najmudin Z, Mori WB, Wahlström CG, Krushelnick K. Laser-wakefield acceleration of monoenergetic electron beams in the first plasma-wave period. PHYSICAL REVIEW LETTERS 2006; 96:215001. [PMID: 16803242 DOI: 10.1103/physrevlett.96.215001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2006] [Indexed: 05/10/2023]
Abstract
Beam profile measurements of laser-wakefield accelerated electron bunches reveal that in the monoenergetic regime the electrons are injected and accelerated at the back of the first period of the plasma wave. With pulse durations ctau >or= lambda(p), we observe an elliptical beam profile with the axis of the ellipse parallel to the axis of the laser polarization. This increase in divergence in the laser polarization direction indicates that the electrons are accelerated within the laser pulse. Reducing the plasma density (decreasing ctau/lambda(p)) leads to a beam profile with less ellipticity, implying that the self-injection occurs at the rear of the first period of the plasma wave. This also demonstrates that the electron bunches are less than a plasma wavelength long, i.e., have a duration <25 fs. This interpretation is supported by 3D particle-in-cell simulations.
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Persson A, Dahlström N, Smedby Ö, Brismar TB. Three-dimensional drip infusion CT cholangiography in patients with suspected obstructive biliary disease: a retrospective analysis of feasibility and adverse reaction to contrast material. BMC Med Imaging 2006; 6:1. [PMID: 16630362 PMCID: PMC1475834 DOI: 10.1186/1471-2342-6-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2005] [Accepted: 04/22/2006] [Indexed: 01/11/2023] Open
Abstract
Background Computed Tomography Cholangiography (CTC) is a fast and widely available alternative technique to visualise hepatobiliary disease in patients with an inconclusive ultrasound when MRI cannot be performed. The method has previously been relatively unknown and sparsely used, due to concerns about adverse reactions and about image quality in patients with impaired hepatic function and thus reduced contrast excretion. In this retrospective study, the feasibility and the frequency of adverse reactions of CTC when using a drip infusion scheme based on bilirubin levels were evaluated. Methods The medical records of patients who had undergone upper abdominal spiral CT with subsequent three-dimensional rendering of the biliary tract by means of CTC during seven years were retrospectively reviewed regarding serum bilirubin concentration, adverse reaction and presence of visible contrast media in the bile ducts at CT examination. In total, 153 consecutive examinations in 142 patients were reviewed. Results Contrast media was observed in the bile ducts at 144 examinations. In 110 examinations, the infusion time had been recorded in the medical records. Among these, 42 examinations had an elevated bilirubin value (>19 umol/L). There were nine patients without contrast excretion; 3 of which had a normal bilirubin value and 6 had an elevated value (25–133 umol/L). Two of the 153 examinations were inconclusive. One subject (0.7%) experienced a minor adverse reaction – a pricking sensation in the face. No other adverse effects were noted. Conclusion We conclude that drip infusion CTC with an infusion rate of the biliary contrast agent iotroxate governed by the serum bilirubin value is a feasible and safe alternative to MRC in patients with and without impaired biliary excretion. In this retrospective study the feasibility and the frequency of adverse reactions when using a drip infusion scheme based on bilirubin levels has been evaluated.
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Persson A, Brismar TB, Lundström C, Dahlström N, Othberg F, Smedby O. Standardized volume rendering for magnetic resonance angiography measurements in the abdominal aorta. Acta Radiol 2006; 47:172-8. [PMID: 16604964 DOI: 10.1080/02841850500445298] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To compare three methods for standardizing volume rendering technique (VRT) protocols by studying aortic diameter measurements in magnetic resonance angiography (MRA) datasets. MATERIAL AND METHODS Datasets from 20 patients previously examined with gadolinium-enhanced MRA and with digital subtraction angiography (DSA) for abdominal aortic aneurysm were retrospectively evaluated by three independent readers. The MRA datasets were viewed using VRT with three different standardized transfer functions: the percentile method (Pc-VRT), the maximum-likelihood method (ML-VRT), and the partial range histogram method (PRH-VRT). The aortic diameters obtained with these three methods were compared with freely chosen VRT parameters (F-VRT) and with maximum intensity projection (MIP) concerning inter-reader variability and agreement with the reference method DSA. RESULTS F-VRT parameters and PRH-VRT gave significantly higher diameter values than DSA, whereas Pc-VRT gave significantly lower values than DSA. The highest interobserver variability was found for F-VRT parameters and MIP, and the lowest for Pc-VRT and PRH-VRT. All standardized VRT methods were significantly superior to both MIP and F-VRT in this respect. The agreement with DSA was best for PRH-VRT, which was the only method with a mean error below 1 mm and which also had the narrowest limits of agreement (95% of cases between 2.1 mm below and 3.1 mm above DSA). CONCLUSION All the standardized VRT methods compare favorably with MIP and VRT with freely selected parameters as regards interobserver variability. The partial range histogram method, although systematically overestimating vessel diameters, gives results closest to those of DSA.
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Ulleryd P, Karlsson L, Lindroth K, Elowson S, Persson A, Eriksson M, Midtvedt AC, van Raalte M, Schewenius M. P17.47 Antibiotic Usage and Hygiene Risk Factors of 17477 Elderly in Long-Term Municipality Care in Va'stra Gbtaland, Sweden - a Point Prevalence Study. J Hosp Infect 2006. [DOI: 10.1016/s0195-6701(06)60318-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Persson A, Dahlström N, Smedby O, Brismar TB. Volume rendering of three-dimensional drip infusion CT cholangiography in patients with suspected obstructive biliary disease: a retrospective study. Br J Radiol 2005; 78:1078-85. [PMID: 16352582 DOI: 10.1259/bjr/14176682] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
The purpose of this study was to evaluate the diagnostic potential of prolonged drip infusion CT cholangiography (DIC-CT) using meglumine iotroxate (Biliscopin) and 3D volume rendering in patients with suspected obstructive biliary disease. From a material of 142 patients who had undergone a drip infusion CT, all cases with a verified surgical or endoscopic retrograde cholangiography (ERC) diagnosis (n=33) were selected. Age-matched controls were selected from the remaining examinations. Three radiologists reviewed all 66 examinations in retrospect, independently as well as in consensus. The image quality and the estimated diagnostic quality were rated as good or moderate in 91% of the 198 reviews. The consensus sensitivity and specificity for diagnosing biliary stones was 88% and 94%, respectively (with sensitivities ranging from 88% to 94% for individual observers, and specificities from 86% to 96%). Two out of three strictures were observed. No false positive strictures were described. The use of volume rendering technique (VRT) improved diagnostic certainty in 28/198 (14%) of the evaluations. The visualization of ductal stones was improved in 18/48 (38%). No differences in diagnostic quality between single and multislice CT were observed. We conclude that a detailed image of the biliary tree with good sensitivity and specificity can be obtained by means of bilirubin-governed infusion time DIC-CT with volume rendering reconstruction.
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Kovacev M, Fomichev SV, Priori E, Mairesse Y, Merdji H, Monchicourt P, Breger P, Norin J, Persson A, L'Huillier A, Wahlström CG, Carré B, Salières P. Extreme ultraviolet Fourier-transform spectroscopy with high order harmonics. PHYSICAL REVIEW LETTERS 2005; 95:223903. [PMID: 16384221 DOI: 10.1103/physrevlett.95.223903] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2005] [Indexed: 05/05/2023]
Abstract
We demonstrate a new scheme for extreme ultraviolet (xuv) Fourier-transform spectroscopy based on the generation of two phase-locked high-harmonic beams. It allows us to measure for the first time interferograms at wavelengths as short as 90 nm, and open the perspective of performing high-resolution Fourier-transform absorption spectroscopy in the xuv. Our measurements also demonstrate that a precise control of the relative phase of harmonic pulses can be obtained with an accuracy on an attosecond time scale, of importance for future xuv pump-xuv probe attosecond spectroscopy.
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Sörstedt E, Persson A, Norén B, Björnlert U, Malcherek P, Axelsson M, Johansson J, Smedby O. Computed tomographic colonography: comparison of two workstations. Acta Radiol 2005; 46:671-8. [PMID: 16372685 DOI: 10.1080/02841850500223109] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
PURPOSE To compare two commercially available computed tomography (CT) colonography systems with respect to interobserver variability, the influence of level of expertise, and the gradual reduction of reviewing time for each system. MATERIAL AND METHODS Two residents and two radiologists using Siemens CTAPP Colography software and Viatronix V3D-Colon software reviewed supine and prone CT acquisitions from 24 patients in a primary 3D endoluminal view. The observers graded each case with respect to technical quality and diagnostic value, assessed the presence of pathology, and indicated the time spent on the viewing. RESULTS Significant differences were found in technical quality (P < 0.001) and diagnostic value (P<0.001) depending on which system was used, with higher scores for the Viatronix software. The agreement between specialists tended to be higher than that between residents (kappa=0.63 (0.30-0.95) vs. kappa=0.51 (0.21-0.81)), and the residents gave significantly (P < 0.001) higher scores of technical quality. However, the level of expertise had no significant impact on the assessments. We noted extensive variability in pathological lesions found by the different observers. The number of findings did not differ between workstations, but the viewers tended to report larger polyp sizes with the Viatronix software. The time needed for viewing decreased significantly from the first to the last examination viewed by each observer. CONCLUSION Both the evaluated systems present trustworthy images of the human colon, but in a primary 3D setting the Viatronix software is favored owing to the user-friendly interface, higher experienced technical quality, and better diagnostic value.
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Lindau F, Lundh O, Persson A, McKenna P, Osvay K, Batani D, Wahlström CG. Laser-accelerated protons with energy-dependent beam direction. PHYSICAL REVIEW LETTERS 2005; 95:175002. [PMID: 16383834 DOI: 10.1103/physrevlett.95.175002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2004] [Indexed: 05/05/2023]
Abstract
The spatial distribution of protons, accelerated by intense femtosecond laser pulses interacting with thin target foils under oblique irradiation are investigated. Under certain conditions, the proton beams are directed away from the target normal. This deviation is towards the laser forward direction, with an angle that increases with the level and duration of the amplified spontaneous emission pedestal before the main laser pulse. In addition, for a given laser pulse, this beam deviation increases with proton energy. The observations are discussed in terms of different electron acceleration mechanisms and target normal sheath acceleration, in combination with a laser-controllable shock wave locally deforming the target rear surface.
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Persson A, Skagerberg G, Salford LG, Englund E. Immunotreatment in patients with glioblastoma multiforme--a histopathological evaluation of reactive and inflammatory changes. Clin Neuropathol 2005; 24:201-8. [PMID: 16167543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/04/2023] Open
Abstract
Glioblastoma multiforme (GBM) is the most common highly malignant brain tumor and is also one among the most therapy-resistant human neoplasias. At the University Hospital in Lund, a group of patients with GBM were treated with a new therapy form attempting immunization by glioma cells transfected to produce interferon-gamma. The purpose of this report was to evaluate tumor material from the first nine patients treated with this therapy, assessing the levels of inflammatory/reactive cells (lymphocytes and macrophages). Tumor biopsies from surgery performed at different time points during treatment were analyzed with conventional histotechnical methods and immunohistochemistry. A post-mortem neuropathological investigation with a whole brain assessment was achieved in 5 immunized patients. The results show that cytotoxic T lymphocytes exhibited a mild increase during immunotreatment. This increase indicates an invoked stimulation of a cytotoxic T cell reaction, which may prove beneficial when immunization is adequately manipulated in dosage and timing.
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Persson A, Lingstrom P, van Dijken JWV. Effect of a Hydroxyl Ion-Releasing Composite Resin on Plaque Acidogenicity. Caries Res 2005; 39:201-6. [PMID: 15914982 DOI: 10.1159/000084799] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2002] [Accepted: 07/14/2004] [Indexed: 11/19/2022] Open
Abstract
The aim of this in vivo study was to evaluate the neutralizing capacity, registered as change of plaque acidogenicity, on aged proximal restorations of an ion-releasing composite resin (IRCR), which releases hydroxyl, calcium, and fluoride ions at low pH. Twenty patients, with a mean age of 63 years (range 43-85), participated. All had one aged proximal IRCR restoration (mean age 15 months) and one nonrestored enamel surface to make an intraindividual comparison possible. The neutralizing effect of the IRCR was evaluated by measuring plaque pH, using the microtouch method, after a mouthrinse with 10% sucrose. The plaque pH measurements were repeated 1.5 years later on the IRCR (mean age 34 months), the enamel surfaces and a universal hybrid composite resin (CR). At both 15 and 34 months, the plaque on the IRCR surfaces showed the least acidogenic potential for the whole 60-min time interval. The largest differences between the IRCR, CR and enamel were found during the first 15 min. At 15 months, the total areas under the plaque pH curve (AUC(5.7) and AUC(6.2)) differed significantly between the IRCR and enamel surfaces for the time periods 0-5 min and 5-15 min. At 34 months, significant differences were found between IRCR and CR at the 0- to 5-min time period. It can be concluded that IRCR restorations countered the plaque pH fall and maintained it at levels where less enamel and dentin demineralization can occur.
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Hanauer S, Sandborn WJ, Persson A, Persson T. Budesonide as maintenance treatment in Crohn's disease: a placebo-controlled trial. Aliment Pharmacol Ther 2005; 21:363-71. [PMID: 15709986 DOI: 10.1111/j.1365-2036.2005.02338.x] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
AIM To assess the efficacy and safety of budesonide capsules 6 mg daily for prolongation of time to relapse and maintenance of remission in patients with Crohn's disease (CD) affecting the ileum and/or ascending colon. METHODS In a double-blind, placebo-controlled, multicentre trial, 110 patients with CD, who had previously achieved remission in a placebo-controlled trial of budesonide 9 mg daily, were randomly assigned to receive budesonide 6 mg once daily or placebo for 52 weeks. Primary outcome measure was time to relapse [CD activity index (CDAI) of >150 plus an increase of at least 60 points from study entry or withdrawal due to clinical deterioration]. RESULTS Median time to relapse was 360 days for budesonide patients; 169 days for placebo patients (P = 0.132). No significant differences were seen between groups in relapse rates at 1 year. Budesonide was safe and well tolerated, with a similar adverse events profile to placebo. CONCLUSION Patients treated with budesonide 6 mg once daily had a trend towards a prolonged time to relapse and lower CDAI scores compared with patients treated with placebo, but relapse rates were not significantly different at the 1-year end point.
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Hultén F, Persson A, Eliasson-Selling L, Heldmer E, Lindberg M, Sjögren U, Kugelberg C, Ehlorsson CJ. Evaluation of environmental and management-related risk factors associated with chronic mastitis in sows. Am J Vet Res 2004; 65:1398-403. [PMID: 15524327 DOI: 10.2460/ajvr.2004.65.1398] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
OBJECTIVE To evaluate environmental and management-related risk factors associated with chronic mastitis in sows. ANIMALS 1,254 sows from 76 herds. PROCEDURE Prevalence of chronic mastitis was determined by a veterinarian who performed clinical examinations at the time of weaning and approximately 1 week later in a sample of the sow population on each farm. Information concerning environmental factors and management practices was collected. In addition, the herd veterinarian made an assessment of the farmer's skills in swine production. RESULTS Use of partly slatted floors in the farrowing pens, use of disinfectants between batches in the farrowing and breeding areas, feeding lactating sows whey, and avoiding cutting or grinding of the piglets' teeth were significantly associated with a decreased risk of chronic mastitis. A high hygienic standard on the farm, as determined by the herd veterinarian, was associated with a significant reduction in the prevalence of mastitis. CONCLUSIONS AND CLINICAL RELEVANCE Chronic mastitis in sows is a common disease that has a negative influence on productivity. Results indicate that certain management practices and environmental factors influenced the development of mastitis, which may contribute to the development of methods useful for controlling the disease.
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Persson A, Dahlström N, Engellau L, Larsson EM, Brismar TB, Smedby O. Volume rendering compared with maximum intensity projection for magnetic resonance angiography measurements of the abdominal aorta. Acta Radiol 2004; 45:453-9. [PMID: 15323400 DOI: 10.1080/02841850410006876] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
PURPOSE To compare the volume rendering technique (VRT) with maximum intensity projection (MIP) for aortic diameter measurements in MR angiography (MRA) data sets. MATERIAL AND METHODS Existing contrast-enhanced 3-dimensional MRA and digital subtraction angiography (DSA) data sets from 20 patients were analyzed. In each MRA data set, two aortic diameters were measured using MIP and VRT. Agreement with DSA measurements, dependence on rendering parameters, and interobserver agreement were assessed. RESULTS Diameters measured on MIP with fixed parameters showed no significant difference compared with DSA and with freely selected parameters a slight overestimation relative to DSA. Diameters measured on VRT were larger than on DSA. For both MIP and VRT, the measurements depended on the chosen parameters. The error relative to DSA was larger for VRT than for MIP with fixed parameters but not with freely chosen parameters. Interobserver agreement did not differ significantly. CONCLUSIONS VRT is not suitable for diameter measurements of the abdominal aorta with fixed parameter settings but may be useful with user-selected settings.
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