| 1. |
- Gustafsson, Håkan, et al.
(författare)
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Magnetic and Electron Spin Relaxation Properties of (GdxY1-x)(2)O-3 (0 <= x <= 1) Nanoparticles Synthesized by the Combustion Method. Increased Electron Spin Relaxation Times with Increasing Yttrium Content
- 2011
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Ingår i: The Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 115:13, s. 5469-5477
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Tidskriftsartikel (refereegranskat)abstract
- The performance of a magnetic resonance imaging contrast agent (CA) depends on several factors, including the relaxation times of the unpaired electrons in the CA. The electron spin relaxation time may be a key factor for the performance of new CAs, such as nanosized Gd2O3 particles. The aim of this work is, therefore, to study changes in the magnetic susceptibility and the electron spin relaxation time of paramagnetic Gd2O3 nanoparticles diluted with increasing amounts of diamagnetic Y2O3. Nanoparticles of (GdxY1-x)(2)O-3 (0 <= x <= 1) were prepared by the combustion method and thoroughly characterized (by X-ray diffraction, transmission electron microscopy, thermogravimetry coupled with mass spectroscopy, photoelectron spectroscopy, Fourier transform infrared spectroscopy, and magnetic susceptibility measurements). Changes in the electron spin relaxation time were estimated by observations of the signal line width in electron paramagnetic resonance spectroscopy, and it was found that the line width was dependent on the concentration of yttrium, indicating that diamagnetic Y2O3 may increase the electron spin relaxation time of Gd2O3 nanoparticles.
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| 2. |
- Gustafsson, Håkan, 1976-, et al.
(författare)
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Magnetic and Electron Spin Relaxation Properties of (GdxY1-x)2O3 (0 ≤ x ≤ 1) Nanoparticles Synthesized by the Combustion Method. Increased Electron Spin Relaxation Times with Increasing Yttrium Content
- 2011
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Ingår i: The Journal of Physical Chemistry C. - United States : American Chemical Society. - 1932-7447 .- 1932-7455. ; 115:13, s. 5469-5477
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Tidskriftsartikel (refereegranskat)abstract
- The performance of a magnetic resonance imaging contrast agent (CA) depends on several factors, including the relaxation times of the unpaired electrons in the CA. The electron spin relaxation time may be a key factor for the performance of new CAs, such as nanosized Gd2O3 particles. The aim of this work is, therefore, to study changes in the magnetic susceptibility and the electron spin relaxation time of paramagnetic Gd2O3 nanoparticles diluted with increasing amounts of diamagnetic Y2O3. Nanoparticles of (GdxY1-x)2O3 (0 e x e 1) were prepared by the combustion method and thoroughly characterized (by X-ray di.raction, transmission electron microscopy, thermogravimetry coupled with mass spectroscopy, photoelectron spectroscopy, Fourier transform infrared spectroscopy, and magnetic susceptibility measurements). Changes in the electron spin relaxation time were estimated by observations of the signal line width in electron paramagnetic resonance spectroscopy, and it was found that the line width was dependent on the concentration of yttrium, indicating that diamagnetic Y2O3 may increase the electron spin relaxation time of Gd2O3 nanoparticles.
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| 3. |
- Björk, Sofie, et al.
(författare)
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Thiopental and decompressive craniectomy as last-tier ICP-treatments in aneurysmal subarachnoid hemorrhage : is functional recovery within reach?
- 2023
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Ingår i: Neurosurgical review. - : Springer Nature. - 0344-5607 .- 1437-2320. ; 46:1
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Tidskriftsartikel (refereegranskat)abstract
- The study aimed to investigate the indication and functional outcome after barbiturates and decompressive craniectomy (DC) as last-tier treatments for elevated intracranial pressure (ICP) in aneurysmal subarachnoid hemorrhage ( aSAH). This observational study included 891 aSAH patients treated at a single center between 2008 and 2018. Data on demography, admission status, radiology, ICP, clinical course, and outcome 1-year post-ictus were collected. Patients treated with thiopental ( barbiturate) and DC were the main target group. Thirty-nine patients (4%) were treated with thiopental alone and 52 (6%) with DC. These patients were younger and had a worse neurological status than those who did not require these treatments. Before thiopental, the median midline shift was 0 mm, whereas basal cisterns were compressed/obliterated in 66%. The median percentage of monitoring time with ICP > 20 mmHg immediately before treatment was 38%, which did not improve after 6 h of infusion. Before DC, the median midline shift was 10 mm, and the median percentage of monitoring time with ICP > 20 mmHg before DC was 56%, which both significantly improved postoperatively. At follow-up, 52% of the patients not given thiopental or operated with DC reached favorable outcome, whereas this occurred in 10% of the thiopental and DC patients. In summary, 10% of the aSAH cohort required thiopental, DC, or both. Thiopental and DC are important integrated last-tier treatment options, but careful patient selection is needed due to the risk of saving many patients into a state of suffering.
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| 4. |
- Engström, Ingemar, 1952-, et al.
(författare)
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Relational continuity may give better clinical outcomes in patients with serious mental illness - a systematic review
- 2023
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Ingår i: BMC Psychiatry. - : BioMed Central (BMC). - 1471-244X. ; 23:1
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Forskningsöversikt (refereegranskat)abstract
- BackgroundContinuity of care is considered important for results of treatment of serious mental illness (SMI). Yet, evidence of associations between relational continuity and different medical and social outcomes is sparse. Research approaches differ considerably regarding how to best assess continuity as well as which outcome to study. It has hitherto been difficult to evaluate the importance of relational continuity of care. The aim of this systematic review was to investigate treatment outcomes, including effects on resource use and costs associated with receiving higher relational continuity of care for patients with SMI.MethodsEleven databases were searched between January 2000 and February 2021 for studies investigating associations between some measure of relational continuity and health outcomes and costs. All eligible studies were assessed for study relevance and risk of bias by at least two independent reviewers. Only studies with acceptable risk of bias were included. Due to study heterogeneity the synthesis was made narratively, without meta-analysis. The certainty of the summarized result was assessed using GRADE. Study registration number in PROSPERO: CRD42020196518.ResultsWe identified 8 916 unique references and included 17 studies comprising around 300 000 patients in the review. The results were described with regard to seven outcomes. The results indicated that higher relational continuity of care for patients with serious mental illness may prevent premature deaths and suicide, may lower the number of emergency department (ED) visits and may contribute to a better quality of life compared to patients receiving lower levels of relational continuity of care. The certainty of the evidence was assessed as low or very low for all outcomes. The certainty of results for the outcomes hospitalization, costs, symptoms and functioning, and adherence to drug treatment was very low with the result that no reliable conclusions could be drawn in these areas.ConclusionsThe results of this systematic review indicate that having higher relational continuity of care may have beneficial effects for patients with severe mental illness, and no results have indicated the opposite relationship. There is a need for better studies using clear and distinctive measures of exposure for relational continuity of care.
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| 5. |
- Engström, Maria, 1968-
(författare)
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Cheruvimskie pesnopenija v russkoj liturgičeskoj tradicii
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis is a contribution to a growing field of studies on the reception of Byzantine culture in Russia. The object of investigation is the history of the Church Slavonic translation of the Cherubika, which constitute one of the most ancient and dogmatically important functional genres of Byzantine liturgical hymns. The chronological frame of this study is the 13th–17th century. Particular attention is focused on the last change in the liturgical texts in Muscovite Russia, in the mid-17th century. This liturgical reform, which led to the famous Schism in the Russian Church, is studied as part of the cultural reforms started by Tsar Alexis Romanov (1645-1676).The most characteristic feature of Orthodoxy is the principal unity of Scripture and Tradition, which in a hermeneutical perspective means the inseparability of text and context. The semiotic and interdisciplinary approach used in this study reflects this principle. The Slavic Cherubika are interpreted in a broad cultural perspective, and Church Slavonic translations are studied in the proper theological, rhetorical and linguistic contexts.Although the 17th-century translations made in Moscow were based on late Greek and South Slavic sources, they reconstruct the original dogmatic message of the Byzantine Cherubika and are hence closer to the Tradition than earlier Slavonic translations.This study offers a new interpretation of the nature of the Schism. It is shown that the main cause of the controversy between Reformists and Old Believers lies in their different understandings of the connection between Text and Ritual. The traditional medieval interpretation of the Cherubika is influenced by certain iconographical themes, other liturgical texts and the priest’s actions during the liturgy. The transition from a liturgocentric interpretation of sacral texts to a descriptive theological interpretation was a break from the characteristic Russian form of liturgocentrism and the beginning of a new cultural era.
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| 6. |
- Engström, Per, 1974-, et al.
(författare)
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Early Interventions and Disability Insurance : Experience from a Field Experiment
- 2017
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Ingår i: Economic Journal. - : Oxford University Press (OUP). - 0013-0133 .- 1468-0297. ; 127, s. 363-392
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Tidskriftsartikel (refereegranskat)abstract
- We estimate the effects of early assessments of an individual's need for vocational rehabilitation in the Swedish sickness insurance system using a field experiment. One of the interventions increases the flow to disability benefits by 20%. The effect is larger for unemployed individuals, who also are covered by the sickness insurance scheme. This result is in line with a theoretical model with moral hazard and asymmetric information in which individuals with low work incentives communicate worse health in response to the assessment for rehabilitation which then increases the hazard to disability benefits.
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| 7. |
- Engström, Per, et al.
(författare)
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The medical doctors as gatekeepers in the sickness insurance?
- 2012
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Ingår i: Applied Economics. - : Informa UK Limited. - 0003-6846 .- 1466-4283. ; 44:28, s. 3615-3625
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Tidskriftsartikel (refereegranskat)abstract
- Based on a randomized experiment, we estimate effects from notification to medical doctors of tighter monitoring of their Medical Certificates (MCs). Both the time prescribed by the doctor certificates for sick leave (prescribed sick leave) and the impact on the length of the actual sickness absence (actual sick leave) is studied. We find no effect on the total number of prescribed sick leave days. However, we do find an increase in both prescribed and actual sick leave with a 25% work inability. We also find that the notification letter causes an increase in actual sick leave (i.e. the number of reimbursed sick days). We discuss a number of potential explanations for this rather surprising result.
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| 8. |
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| 9. |
- Ganowiak, Katarzyna, et al.
(författare)
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Fibrils from Synthetic Amyloid-Related Peptides Enhance Development of Experimental AA-Amyloidosis in Mice
- 1994
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Ingår i: Biochemical and Biophysical Research Communications - BBRC. - : Elsevier BV. - 0006-291X .- 1090-2104. ; 199:1, s. 306-312
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Tidskriftsartikel (refereegranskat)abstract
- Amyloid enhancing factor is an incompletely characterized activity of extracts from many amyloid-containing tissues and which greatly shortens the preamyloidotic phase during experimental induction of AA-amyloidosis. In this communication we show that amyloid-like fibrils made in vitro from synthetic peptides, corresponding to segments of amyloid fibril proteins, have amyloid enhancing factor-like activity. Thus, there is a possibility that amyloid enhancing factor activity depends on small fibrils serving as nucleation centers for fibril elongation.
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| 10. |
- Gebre-Medhin, Maria, et al.
(författare)
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ARTSCAN III : A randomized phase III study comparing chemoradiotherapy with cisplatin versus cetuximab in patients with locoregionally advanced head and neck squamous cell cancer
- 2021
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Ingår i: Journal of Clinical Oncology. - : American Society of Clinical Oncology. - 0732-183X .- 1527-7755. ; 39:1, s. 38-47
-
Tidskriftsartikel (refereegranskat)abstract
- PURPOSE We performed an open-label randomized controlled phase III study comparing treatment outcome and toxicity between radiotherapy (RT) with concomitant cisplatin versus concomitant cetuximab in patients with locoregionally advanced head and neck squamous cell carcinoma (HNSCC; stage III-IV according to the Union for International Cancer Control TNM classification, 7th edition). MATERIALS AND METHODS Eligible patients were randomly assigned 1:1 to receive either intravenous cetuximab 400 mg/m2 1 week before start of RT followed by 250 mg/m2/wk, or weekly intravenous cisplatin 40 mg/m2, during RT. RT was conventionally fractionated. Patients with T3-T4 tumors underwent a second random assignment 1:1 between standard RT dose 68.0 Gy to the primary tumor or dose escalation to 73.1 Gy. Primary end point was overall survival (OS) evaluated using adjusted Cox regression analysis. Secondary end points were locoregional control, local control with dose-escalated RT, pattern of failure, and adverse effects. RESULTS Study inclusion was prematurely closed after an unplanned interim analysis when 298 patients had been randomly assigned. At 3 years, OS was 88% (95% CI, 83% to 94%) and 78% (95% CI, 71% to 85%) in the cisplatin and cetuximab groups, respectively (adjusted hazard ratio, 1.63; 95% CI, 0.93 to 2.86; P 5 .086). The cumulative incidence of locoregional failures at 3 years was 23% (95% CI, 16% to 31%) compared with 9% (95% CI, 4% to 14%) in the cetuximab versus the cisplatin group (Gray’s test P 5 .0036). The cumulative incidence of distant failures did not differ between the treatment groups. Dose escalation in T3-T4 tumors did not increase local control. CONCLUSION Cetuximab is inferior to cisplatin regarding locoregional control for concomitant treatment with RT in patients with locoregionally advanced HNSCC. Additional studies are needed to identify possible subgroups that still may benefit from concomitant cetuximab treatment.
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| 11. |
- Gustafsson, Per E, 1981-
(författare)
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Psychosocial Stress, Mental Health and Salivary Cortisol in Children and Adolescents
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Stressful experiences and conditions in childhood influence the health and well-being of the growing individual, and can also confer a long-lasting impact into adult life. Delineating the social, mental and biological aspects of stress in children and adolescents is therefore of great concern for human beings. Despite these notions, much knowledge is lacking regarding stress in childhood.This thesis aimed at examining diverse aspects of stress in children and adolescents: associations between social conditions, traumatic life events, mental health, and salivary cortisol as a measure of the activity of a major physiological stress system. Cross-sectional samples included two non-clinical samples of school-aged children (N=240-336) and adolescents (N =400), and two clinical samples of children with obsessive-compulsive disorder (OCD) (N =23) and adolescents who had experienced childhood abuse (N =15). Main measures were salivary cortisol sampled three times a day, and questionnaires to teachers, parents and children with questions about each child’s mental health, traumatic life events and about the socioeconomic situation of the parents.The main findings include observation of 1) higher cortisol levels in children with a moderate level of psychosocial burden (low socioeconomic status, immigrant family, social impairment of mental health problems), 2) higher cortisol levels in children with OCD who also displayed a tendency to decreasing cortisol in the face of an acute stressor, and 3) cortisol was positively related to mental health problems in abused adolescents. Furthermore, the deleterious effect of 4) traumatic events involving a social dimension, interpersonal traumas, and 5) cumulative traumatic events, polytraumatization, on the mental health of children and adolescents was indicated.The findings are discussed with respect to the complex interactions between social, mental and biological aspects of children and adolescents. The consequences of adverse experiences in childhood may represent pathways to future health problems. Consideration of the social circumstances in childhood might in the future guide public health policies and the identification of target groups for preventive interventions as well as leading to improvements in treatment for children exposed to severe stress.
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| 12. |
- Johan, Katarzyna, et al.
(författare)
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Acceleration of amyloid protein A amyloidosis by amyloid-like synthetic fibrils
- 1998
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - 0027-8424 .- 1091-6490. ; 95:5, s. 2558-2563
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Tidskriftsartikel (refereegranskat)abstract
- Amyloid protein A (AA) amyloidosis is a consequence of some long-standing inflammatory conditions, and subsequently, an N-terminal fragment of the acute phase protein serum AA forms β-sheet fibrils that are deposited in different tissues. It is unknown why only some individuals develop AA amyloidosis. In the mouse model, AA amyloidosis develops after ≈25 days of inflammatory challenge. This lag phase can be shortened dramatically by administration of a small amount of amyloid extract containing an as yet undefined amyloid-enhancing factor. In the present study, we show that preformed amyloid-like fibrils made from short synthetic peptides corresponding to parts of several different amyloid fibril proteins exert amyloidogenic enhancing activity when given i.v. to mice at the induction of inflammation. We followed i.v. administered, radiolabeled, heterologous, synthetic fibrils to the lung and to the perifollicular area in the spleen and found that new AA–amyloid fibrils developed on these preformed fibrils. Our findings thus show that preformed, synthetic, amyloid-like fibrils have an in vivo nidus activity and that amyloid-enhancing activity may occur, at least in part, through this mechanism. Our findings also show that fibrils of a heterologous chemical nature exert amyloid-enhancing activity.
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| 13. |
- Mathern, Alexandre, 1986, et al.
(författare)
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Enhanced strut-and-tie model for reinforced concrete pile caps
- 2017
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Ingår i: IABSE Conference, Vancouver 2017: Engineering the Future - Report. ; , s. 607-614
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Konferensbidrag (refereegranskat)abstract
- Strut-and-tie models provide a simple and rational way to design discontinuity regions in reinforced concrete structures. However, when it comes to three-dimensional concrete elements such as pile caps, enhancements are needed to ensure a reliable and not overly conservative design. This paper presents an enhanced strut-and-tie model adapted to the analysis and design of reinforced concrete pile caps. The model is based on consistent geometries of three-dimensional nodal zones and struts and integrates a strength criterion for confined bottle-shaped struts. An iterative process is used in order to optimize the position of the members by refining the dimensions of the nodal zones. The model is validated by experimental results from tests on four-pile caps reported in the literature, showing effective predictions of their ultimate capacities. This enhanced strut-and-tie model can lead to safe and less conservative design of pile caps.
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| 14. |
- Petersson, Kristoffer, et al.
(författare)
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Conversion of helical tomotherapy plans to step-and-shoot IMRT plans-Pareto front evaluation of plans from a new treatment planning system
- 2011
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Ingår i: Medical Physics. - : Wiley. - 0094-2405. ; 38:6, s. 3130-3138
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: The resulting plans from a new type of treatment planning system called SharePlan (TM) have been studied. This software allows for the conversion of treatment plans generated in a TomoTherapy system for helical delivery, into plans deliverable on C-arm linear accelerators (linacs), which is of particular interest for clinics with a single TomoTherapy unit. The purpose of this work was to evaluate and compare the plans generated in the SharePlan system with the original TomoTherapy plans and with plans produced in our clinical treatment planning system for intensity-modulated radiation therapy (IMRT) on C-arm linacs. In addition, we have analyzed how the agreement between SharePlan and TomoTherapy plans depends on the number of beams and the total number of segments used in the optimization. Methods: Optimized plans were generated for three prostate and three head-and-neck (H&N) cases in the TomoTherapy system, and in our clinical treatment planning systems (TPS) used for IMRT planning with step-and-shoot delivery. The TomoTherapy plans were converted into step-and-shoot IMRT plans in SharePlan. For each case, a large number of Pareto optimal plans were created to compare plans generated in SharePlan with plans generated in the Tomotherapy system and in the clinical TPS. In addition, plans were generated in SharePlan for the three head-and-neck cases to evaluate how the plan quality varied with the number of beams used. Plans were also generated with different number of beams and segments for other patient cases. This allowed for an evaluation of how to minimize the number of required segments in the converted IMRT plans without compromising the agreement between them and the original TomoTherapy plans. Results: The plans made in SharePlan were as good as or better than plans from our clinical system, but they were not as good as the original TomoTherapy plans. This was true for both the head-and-neck and the prostate cases, although the differences between the plans for the latter were small. The evaluation of the head-and-neck cases also showed that the plans generated in SharePlan were improved when more beams were used. The SharePlan Pareto front came close to the front for the TomoTherapy system when a sufficient number of beams were added. The results for plans generated with varied number of beams and segments demonstrated that the number of segments could be minimized with maintained agreement between SharePlan and TomoTherapy plans when 10-19 beams were used. Conclusions: This study showed (using Pareto front evaluation) that the plans generated in SharePlan are comparable to plans generated in other TPSs. The evaluation also showed that the plans generated in SharePlan could be improved with the use of more beams. To minimize the number of segments needed in a plan with maintained agreement between the converted IMRT plans and the original TomoTherapy plans, 10-19 beams should be used, depending on target complexity. SharePlan has proved to be useful and should thereby be a time-saving complement as a backup system for clinics with a single TomoTherapy system installed alongside conventional C-arm linacs. (C) 2011 American Association of Physicists in Medicine. [DOI: 10.1118/1.3592934]
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| 15. |
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| 16. |
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| 17. |
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| 18. |
- Petersson, Kristoffer, et al.
(författare)
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Treatment plan comparison using grading analysis based on clinical judgment.
- 2013
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Ingår i: Acta Oncologica. - 1651-226X. ; 52:3, s. 645-651
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Tidskriftsartikel (refereegranskat)abstract
- Purpose. In this work we explore a method named clinical grading analysis (CGA) which is based on clinical assessments performed by radiation oncologists (ROs). The purpose is to investigate how useful the method is for treatment plan comparisons, and how the CGA results correlate with dosimetric evaluation parameters, traditionally used for treatment plan comparisons. Material and methods. Helical tomotherapy (HTT) and seven-beam step-and-shoot intensity modulated radiation therapy (SS-IMRT) plans were compared and assessed by 10 experienced ROs for 23 patient cases. A CGA was performed where the plans were graded based on how the ROs thought they compared to each other. The resulting grades from the CGA were analyzed and compared to dose-volume statistics and equivalent uniform dose (EUD) data. Results. For eight of the 23 cases the CGA revealed a significant difference between the HTT and the SS-IMRT plans, five cases were in favor of HTT, and three in favor of SS-IMRT. Comparing the dose-volume statistics and EUD-data with the result from the CGA showed that CGA results correlated well with dose-volume statistics for cases regarding difference in target coverage or doses to organs at risk. The CGA results also correlated well with EUD-data for cases with difference in clinical target volume (CTV) coverage but the correlation for cases with difference in planning target volume (PTV) coverage was not as clear. Conclusions. This study presents CGA as a useful method of comparing radiotherapy treatment plans. The proposed method offers a formalized way of introducing and evaluating the implementation of new radiotherapy techniques in a clinical setting. The CGA identify patients that have a clinical benefit of one or the other of the advanced treatment techniques available to them, i.e. in this study HTT and SS-IMRT, which facilitates a more optimal use of a clinics' advanced treatment resources.
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| 19. |
- Sundström, Johan, Professor, 1971-, et al.
(författare)
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Risk factors for subarachnoid haemorrhage : a nationwide cohort of 950 000 adults
- 2019
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Ingår i: International Journal of Epidemiology. - : Oxford University Press. - 0300-5771 .- 1464-3685. ; 48:6, s. 2018-2025
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Subarachnoid haemorrhage (SAH) is a devastating disease, with high mortality rate and substantial disability among survivors. Its causes are poorly understood. We aimed to investigate risk factors for SAH using a novel nationwide cohort consortium.METHODS: We obtained individual participant data of 949 683 persons (330 334 women) between 25 and 90 years old, with no history of SAH at baseline, from 21 population-based cohorts. Outcomes were obtained from the Swedish Patient and Causes of Death Registries.RESULTS: During 13 704 959 person-years of follow-up, 2659 cases of first-ever fatal or non-fatal SAH occurred, with an age-standardized incidence rate of 9.0 [95% confidence interval (CI) (7.4-10.6)/100 000 person-years] in men and 13.8 [(11.4-16.2)/100 000 person-years] in women. The incidence rate increased exponentially with higher age. In multivariable-adjusted Poisson models, marked sex interactions for current smoking and body mass index (BMI) were observed. Current smoking conferred a rate ratio (RR) of 2.24 (95% CI 1.95-2.57) in women and 1.62 (1.47-1.79) in men. One standard deviation higher BMI was associated with an RR of 0.86 (0.81-0.92) in women and 1.02 (0.96-1.08) in men. Higher blood pressure and lower education level were also associated with higher risk of SAH.CONCLUSIONS: The risk of SAH is 45% higher in women than in men, with substantial sex differences in risk factor strengths. In particular, a markedly stronger adverse effect of smoking in women may motivate targeted public health initiatives.
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| 20. |
- Zetterling, Maria, 1966-, et al.
(författare)
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Cortisol and ACTH dynamics in the acute phase of subarachnoid haemorrhage
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Ingår i: British Journal of Neurosurgery. - 0268-8697 .- 1360-046X.
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Tidskriftsartikel (refereegranskat)abstract
- Objective: An adequate response of hypothalamic-pituitary-adrenal (HPA) axis is important for survival and recovery after a severe disease. The hypothalamus and the pituitary glands are at risk of damage after subarachnoid haemorrhage (SAH). A better understanding of the hormonal changes would be valuable for optimizing care in the acute phase of SAH. Patients: 55 patients with spontaneous SAH were evaluated regarding morning levels of S-Cortisol and P-ACTH seven days after the bleeding. In a subgroup of 20 patients the diurnal changes of S-Cortisol and P-ACTH levels were studied and U-Cortisol measured. The relations of hormone levels to clinical and radiological parameters and to outcome were assessed. Results: S-Cortisol and P-ACTH were elevated the day of SAH. S-Cortisol levels below reference range were uncommon. Early global cerebral oedema was associated with higher S-Cortisol concentrations at admission and a worse WFNS and RLS85 grade. Patients in better WFNS grade had higher U-Cortisol levels. All patients showed diurnal variations of S-Cortisol and P-ACTH. A reversed diurnal variation of S-Cortisol was more frequently seen in mechanically ventilated patients. Periods of suppressed P-ACTH associated with S-Cortisol peaks occurred especially in periods of secondary brain ischemia. Conclusion: There is a HPA response acutely after SAH with an increase of P-ACTH and S-Cortisol levels. Higher U-Cortisol levels in patients in a better clinical grade may indicate a more robust response of the HPA system. Global cerebral oedema was associated with higher S-Cortisol levels at admission and may be the result of the stress response initiated by the brain injury. Periods of suppressed P-ACTH occurred particularly in periods of brain ischemia, indicating a possibly connection between brain ischemia and ACTH suppression. These two novel findings should be evaluated in further studies.
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| 21. |
- Zetterling, Maria, et al.
(författare)
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Cortisol and adrenocorticotropic hormone dynamics in the acute phase of subarachnoid haemorrhage
- 2011
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Ingår i: British Journal of Neurosurgery. - : Informa UK Limited. - 0268-8697 .- 1360-046X. ; 25:6, s. 684-692
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Tidskriftsartikel (refereegranskat)abstract
- Objective. An adequate response of hypothalamic-pituitary-adrenal (HPA) axis is important for survival and recovery after a severe disease. The hypothalamus and the pituitary glands are at risk of damage after subarachnoid haemorrhage (SAH). A better understanding of the hormonal changes would be valuable for optimising care in the acute phase of SAH. Patients. Fifty-five patients with spontaneous SAH were evaluated regarding morning concentrations of serum (S)-cortisol and P-adrenocorticotropic hormone (ACTH) 7 days after the bleeding. In a subgroup of 20 patients, the diurnal changes of S-cortisol and P-ACTH were studied and urine (U)-cortisol was measured. The relationships of hormone concentrations to clinical and radiological parameters and to outcome were assessed. Results. S-cortisol and P-ACTH were elevated the day of SAH. S-cortisol concentrations below reference range were uncommon. Early global cerebral oedema was associated with higher S-cortisol concentrations at admission and a worse World Federation of Neurological Surgeons (WFNS) and Reaction Level Scale 85 grade. Global cerebral oedema was shown to be a predictor of S-cortisol at admittance. Patients in better WFNS grade displayed higher U-cortisol. All patients showed diurnal variations of S-cortisol and P-ACTH. A reversed diurnal variation of S-cortisol was more frequently found in mechanically ventilated patients. Periods of suppressed P-ACTH associated with S-cortisol peaks occurred especially in periods of secondary brain ischaemia. Conclusion. There was an HPA response acutely after SAH with an increase in P-ACTH and S-cortisol. Higher U-cortisol in patients in a better clinical grade may indicate a more robust response of the HPA system. Global cerebral oedema was associated with higher S-cortisol at admission and was a predictor of S-cortisol concentrations. Global cerebral oedema may be the result of the stress response initiated by the brain injury. Periods of suppressed P-ACTH occurred particularly in periods of brain ischaemia, indicating a possible connection between brain ischaemia and ACTH suppression.
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| 22. |
- Östblad, Per Anders, et al.
(författare)
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Inclusive game design : audio interface in a graphical adventure game
- 2014
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Ingår i: 9th Audio Mostly. - New York, USA : ACM Digital Library. - 9781450330329 ; , s. 8-
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Konferensbidrag (refereegranskat)abstract
- A lot of video games on the market are inaccessible to players with visual impairments because they rely heavily on use of graphical elements. This paper presents a project aimed at developing a point-and-click adventure game for smart phones and tablets that is equally functional and enjoyable by blind and sighted players. This will be achieved by utilizing audio to give blind players all necessary information and enjoyment without graphics. In addition to creating the game, the aim of the project is to identify design aspects that can be applied to more types of games to include more players. This paper also presents a pilot study that has been conducted on an early version of the game and the preliminary findings are discussed.
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| 23. |
- Aaltonen, H. Laura, et al.
(författare)
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Airspace dimension assessment with nanoparticles as a proposed biomarker for emphysema
- 2021
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Ingår i: Thorax. - : BMJ. - 0040-6376 .- 1468-3296. ; 76:10, s. 1040-1043
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Tidskriftsartikel (refereegranskat)abstract
- Airspace dimension assessment with nanoparticles (AiDA) is a novel method to measure distal airspace radius non-invasively. In this study, AiDA radii were measured in 618 individuals from the population-based Swedish CArdiopulmonary BioImaging Study, SCAPIS. Subjects with emphysema detected by computed tomography were compared to non-emphysematous subjects. The 47 individuals with mainly mild-to-moderate visually detected emphysema had significantly larger AiDA radii, compared with non-emphysematous subjects (326±48 μm vs 291±36 μm); OR for emphysema per 10 μm: 1.22 (1.13-1.30, p<0.0001). Emphysema according to CT densitometry was similarly associated with larger radii compared with non-emphysematous CT examinations (316±41 μm vs 291 μm±26 μm); OR per 10 μm: 1.16 (1.08-1.24, p<0.0001). The results are in line with comparable studies. The results show that AiDA is a potential biomarker for emphysema in individuals in the general population.
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- Ahrén, Maria, et al.
(författare)
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Synthesis and Characterization of PEGylated Gd2O3 Nanoparticles for MRI Contrast Enhancement
- 2010
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Ingår i: Langmuir. - : American Chemical Society (ACS). - 0743-7463 .- 1520-5827. ; 26:8, s. 5753-5762
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Tidskriftsartikel (refereegranskat)abstract
- Recently, much attention has been given to the development of biofunctionalized nanoparticles with magnetic properties for novel biomedical imaging. Guided, smart, targeting nanoparticulate magnetic resonance imaging (MRI) contrast agents inducing high MRI signal will be valuable tools for future tissue specific imaging and investigation of molecular and cellular events. In this study. We report a new design of functionalized ultrasmall rare earth based nanoparticles to be used as a positive contrast agent in NI RI. The relaxivity is compared to commercially available Gd based chelates. The synthesis, PEGylation, and dialysis of small (3-5 nm) gadolinium oxide (DEG-Gd2O3) nanoparticles are presented. The chemical and physical properties of the nanomaterial were investigated with Fourier transform infrared spectroscopy. X-ray photoelectron spectroscopy, transmission electron microscopy, and dynamic light scattering. Neutrophil activation after exposure to this nanomaterial was studied by means of fluorescence microscopy. The proton relaxation times as a function of dialysis time and functionalization were measured at 1.5 T. A capping procedure introducing stabilizing properties was designed and verified, and the dialysis effects were evaluated. A higher proton relaxivity was obtained for as-synthesized diethylene glycol (DEG)-Gd2O3 nanoparticles compared to commercial Gd-DTPA. A slight decrease of the relaxivity for as-synthesized DEG-Gd2O3 nanoparticles as a function of dialysis time was observed. The results for functionalized nanoparticles showed a considerable relaxivity increase for particles dialyzed extensively with r(1) and r(2) values approximately 4 times the corresponding values for Gd-DTPA. The microscopy study showed that PEGylated nanoparticles do not activate neutrophils in contrast to uncapped Gd2O3. Finally, the nanoparticles are equipped with Rhodamine to show that our PEGylated nanoparticles are available for further coupling chemistry, and thus prepared for targeting purposes. The long term goal is to design a powerful, directed contrast agent for MRI examinations with specific targeting possibilities and with properties inducing local contrast, that is. an extremely high MR signal at the cellular and molecular level.
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