| 1. |
- Spühler, Jeannette H., et al.
(författare)
-
3D Fluid-Structure Interaction Simulation of Aortic Valves Using a Unified Continuum ALE FEM Model
- 2018
-
Ingår i: Frontiers in Physiology. - : Frontiers Media S.A.. - 1664-042X. ; 9
-
Tidskriftsartikel (refereegranskat)abstract
- Due to advances in medical imaging, computational fluid dynamics algorithms and high performance computing, computer simulation is developing into an important tool for understanding the relationship between cardiovascular diseases and intraventricular blood flow. The field of cardiac flow simulation is challenging and highly interdisciplinary. We apply a computational framework for automated solutions of partial differential equations using Finite Element Methods where any mathematical description directly can be translated to code. This allows us to develop a cardiac model where specific properties of the heart such as fluid-structure interaction of the aortic valve can be added in a modular way without extensive efforts. In previous work, we simulated the blood flow in the left ventricle of the heart. In this paper, we extend this model by placing prototypes of both a native and a mechanical aortic valve in the outflow region of the left ventricle. Numerical simulation of the blood flow in the vicinity of the valve offers the possibility to improve the treatment of aortic valve diseases as aortic stenosis (narrowing of the valve opening) or regurgitation (leaking) and to optimize the design of prosthetic heart valves in a controlled and specific way. The fluid-structure interaction and contact problem are formulated in a unified continuum model using the conservation laws for mass and momentum and a phase function. The discretization is based on an Arbitrary Lagrangian-Eulerian space-time finite element method with streamline diffusion stabilization, and it is implemented in the open source software Unicorn which shows near optimal scaling up to thousands of cores. Computational results are presented to demonstrate the capability of our framework.
|
|
| 2. |
- Sarwar, Nadeem, et al.
(författare)
-
Interleukin-6 receptor pathways in coronary heart disease : a collaborative meta-analysis of 82 studies
- 2012
-
Ingår i: The Lancet. - New York, NY, USA : Elsevier. - 0140-6736 .- 1474-547X. ; 379:9822, s. 1205-1213
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Persistent inflammation has been proposed to contribute to various stages in the pathogenesis of cardiovascular disease. Interleukin-6 receptor (IL6R) signalling propagates downstream inflammation cascades. To assess whether this pathway is causally relevant to coronary heart disease, we studied a functional genetic variant known to affect IL6R signalling. Methods: In a collaborative meta-analysis, we studied Asp358Ala (rs2228145) in IL6R in relation to a panel of conventional risk factors and inflammation biomarkers in 125 222 participants. We also compared the frequency of Asp358Ala in 51 441 patients with coronary heart disease and in 136 226 controls. To gain insight into possible mechanisms, we assessed Asp358Ala in relation to localised gene expression and to postlipopolysaccharide stimulation of interleukin 6. Findings: The minor allele frequency of Asp358Ala was 39%. Asp358Ala was not associated with lipid concentrations, blood pressure, adiposity, dysglycaemia, or smoking (p value for association per minor allele >= 0.04 for each). By contrast, for every copy of 358Ala inherited, mean concentration of IL6R increased by 34.3% (95% CI 30.4-38.2) and of interleukin 6 by 14.6% (10.7-18.4), and mean concentration of C-reactive protein was reduced by 7.5% (5.9-9.1) and of fibrinogen by 1.0% (0.7-1.3). For every copy of 358Ala inherited, risk of coronary heart disease was reduced by 3.4% (1.8-5.0). Asp358Ala was not related to IL6R mRNA levels or interleukin-6 production in monocytes. Interpretation: Large-scale human genetic and biomarker data are consistent with a causal association between IL6R-related pathways and coronary heart disease.
|
|
| 3. |
- Sundström, Johan, Professor, 1971-, et al.
(författare)
-
Weight gain and blood pressure
- 2020
-
Ingår i: Journal of Hypertension. - : Lippincott Williams & Wilkins. - 0263-6352 .- 1473-5598. ; 38:3, s. 387-394
-
Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Although the causality of the obesity—hypertension association is established, the potential for prevention is not. We hypothesized that weight gain between early adulthood and mid-life is associated with higher mid-life blood pressure.METHODS: We investigated the hypothesis using a large contemporaneous population-based mid-life cohort of men and women aged 50-64 years. Recalled body weight at age 20 years was self-reported, and mid-life body weight and office blood pressures were measured in accordance with a detailed protocol.RESULTS: On average, men had gained 14.9 (95% CI 14.6-15.2) kg of weight, and women 14.6 (95% CI 14.4-14.9) kg, between age 20 years and the mid-life examination, corresponding to 0.40 (95% CI 0.39-0.41) kg/year for men and women. Both weight at age 20 years and weight at the mid-life examination were associated with mid-life blood pressures. On average, a 10 kg weight increase between age 20 years and mid-life was associated with 2.2 (95% CI 0.9-3.5) mmHg higher systolic and 1.7 (95% CI 0.9-2.5) mmHg higher diastolic mid-life blood pressure in men, and 3.2 (2.5-4.0) mmHg higher systolic and 2.4 (1.9-2.9) mmHg higher diastolic mid-life blood pressure in women. Mid-life weight was more closely associated than weight at age 20 years with mid-life blood pressure. For a given mid-life weight, blood pressure was higher in persons with higher weight gain from age 20 years.CONCLUSION: In sum, weight gain between early adulthood and mid-life was associated with higher mid-life blood pressure. The magnitude of the association indicates a potentially great public health impact of strategies to prevent weight gain throughout adulthood.
|
|
| 4. |
- Jansson, Jan-Håkan, et al.
(författare)
-
Snus (Swedish smokeless tobacco) use and risk of stroke: pooled analyses of incidence and survival
- 2014
-
Ingår i: Journal of Internal Medicine. - : Wiley. - 1365-2796 .- 0954-6820. ; 276:1, s. 87-95
-
Tidskriftsartikel (refereegranskat)abstract
- Background. Snus is a moist smokeless tobacco product with high nicotine content. Its use has a short-term effect on the cardiovascular system, but the relationship between snus use and stroke is unclear. Objective. The aim of this study was to assess the associations between use of snus and incidence of and survival after stroke, both overall and according to subtypes. Methods. Pooled analyses of eight Swedish prospective cohort studies were conducted, including 130 485 men who never smoked. We estimated hazard ratios (HRs) with 95% confidence intervals (CIs) of incidence and death after diagnosis using Cox proportional hazard regression models and case fatality and survival using logistic regression and Kaplan-Meier methods, respectively. Results. No associations were observed between the use of snus and the risk of overall stroke (HR 1.04, 95% CI 0.92-1.17) or of any of the stroke subtypes. The odds ratio (OR) of 28-day case fatality was 1.42 (95% CI 0.99-2.04) amongst users of snus who had experienced a stroke, and the HR of death during the follow-up period was 1.32 (95% CI 1.08-1.61). Conclusion. Use of snus was not associated with the risk of stroke. Hence, nicotine is unlikely to contribute importantly to the pathophysiology of stroke. However, case fatality was increased in snus users, compared with nonusers, but further studies are needed to determine any possible causal mechanisms.
|
|
| 5. |
- Lyth, Johan, 1980-, et al.
(författare)
-
Trends in cutaneous malignant melanoma in Sweden 1997-2011: Thinner tumours and improved survival among men
- 2015
-
Ingår i: British Journal of Dermatology. - : Wiley-Blackwell. - 0007-0963 .- 1365-2133. ; 172:3, s. 700-706
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Both patient survival and the proportion of patients diagnosed with thin cutaneous malignant melanoma (CMM) have been steadily rising in Sweden as in most western countries, though the rate of improvement in survival appears to have declined in Sweden at the end of last millennium.Objectives: To analyse the most recent trends in the distribution of tumour thickness (T-category) as well as CMM-specific survival in Swedish patients diagnosed 1997-2011.Methods: This nationwide population-based study included 30 590 patients registered in the Swedish Melanoma Register (SMR) and diagnosed with a first primary invasive CMM 1997-2011. The patients were followed through 2012 in the national Cause-of-Death Register.Results: Logistic and Cox regression analyses adjusting for age at diagnosis, tumour site, and health care region were carried out. The odds ratio for being diagnosed with thicker tumours was significantly reduced (P = 0·0008) and the CMM-specific survival significantly improved in men diagnosed 2007-2011 compared to men diagnosed 1997-2001 (hazard ratio=0·81; 95% CI 0·72-0·91, P = 0·0009) while the corresponding differences for women were not significant. Women were diagnosed with significantly thicker tumours during 2002-2006 and a tendency towards decreased survival was observed compared to those diagnosed earlier 1997-2001 and later 2007-2011.Conclusion: In Sweden, the CMMs of men are detected earlier over time and this seems to be followed by an improved CMM-specific survival for men. Women are still diagnosed with considerably thinner tumours and they experience a better survival than men.
|
|
| 6. |
- Flyborg, Johan
(författare)
-
The use of the intelligent powered toothbrush in health technology
- 2022
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- BackgroundApplied health technology is a research field that ties together several disciplines to improve and preserve the health and quality of life of individuals and society. Helping especially elderly to meet the above goals is an important and necessary task and assistive technology and collection of health data are part of this work.AimsPaper I aims to investigate whether the use of a powered toothbrush could maintain oral health in a group of individuals with MCI and if changes in oral health affect various aspects of quality of life. Paper II and III aims to examine the capacity of a powered toothbrush as a carrier and mediator of health-related data.MethodsFor papers I and II, the participants were recruited from the Swedish site of the multicenter project Support Monitoring And Reminder Technology for Mild Dementia and for paper III from the Department of Health at Blekinge Institute of Technology. In all three papers, a powered toothbrush has been used as a tool, sensor carrier and transmitter of data. For Quality-of-life assessment two instruments are used, The QoL-AD and OHIP 14.ResultsBy introducing an intelligent powered toothbrush in the group of older individuals with mild cognitive impairment we have showed that they, regardless of cognitive level,improved their scores for plaque index, bleeding index and deepened periodontal pockets ≥ 4mm, over 12 months. The quality-of-life instrument related to oral health improved in parallel with the improvement in oral health. Furthermore, it is possible to use the intelligent powered toothbrush both as a carrier for healt related sensors and to transfer user data via Bluetooth technology to a single-core processor that stores or forwards the data via Wifi to an external computer for processing, analysis and storage. A fesibility study regarding temperature sensor for measuring body temperature during toothbrushing have been evaluated and found to be comparable to traditional oral temperature measurement. ConclusionsAn intelligent powered toothbrush is a well-functioning tool for maintaining oral health in older people with mild cognitive impairment as well as for collecting and transferring brush and health data to external units for storage and analysis.
|
|
| 7. |
- Naeser, Ylva, et al.
(författare)
-
TRIM study protocol - a prospective randomized multicenter Trial to assess the Role of Imaging during follow-up after radical surgery of stage IIB-C and III cutaneous malignant Melanoma
- 2020
-
Ingår i: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 20:1
-
Tidskriftsartikel (refereegranskat)abstract
- BackgroundThe incidence of cutaneous malignant melanoma (CMM) is increasing worldwide. In Sweden, over 4600 cases were diagnosed in 2018. The prognosis after radical surgery varies considerably with tumor stage. In recent years, new treatment options have become available for metastatic CMM. Early onset of treatment seems to improve outcome, which suggests that early detection of recurrent disease should be beneficial. Consequently, in several countries imaging is a part of the routine follow-up program after surgery of high risk CMM. However, imaging has drawbacks, including resources required (costs, personnel, equipment) and the radiation exposure. Furthermore, many patients experience anxiety in waiting for the imaging results and investigations of irrelevant findings is another factor that also could cause worry and lead to decreased quality of life. Hence, the impact of imaging in this setting is important to address and no randomized study has previously been conducted. The Swedish national guidelines stipulate follow-up for 3years by clinical examinations only.MethodsThe TRIM study is a prospective randomized multicenter trial evaluating the potential benefit of imaging and blood tests during follow-up after radical surgery for high-risk CMM, compared to clinical examinations only. Primary endpoint is overall survival (OS) at 5years. Secondary endpoints are survival from diagnosis of relapse and health-related quality of life (HRQoL). Eligible for inclusion are patients radically operated for CMM stage IIB-C or III with sufficient renal function for iv contrast-enhanced CT and who are expected to be fit for treatment in case of recurrence. The planned number of patients is >1300. Patients are randomized to clinical examinations for 3years +/- whole-body imaging with CT or FDG-PET/CT and laboratory tests including S100B protein and LDH. This academic study is supported by the Swedish Melanoma Study Group.DiscussionThis is the first randomized prospective trial on the potential benefit of imaging as a part of the follow-up scheme after radical surgery for high-risk CMM.ResultsThe first patient was recruited in June 2017 and as of April 2020, almost 500 patients had been included at 19 centers in Sweden.Trial registrationClinicalTrials.gov, NCT 03116412. Registered 17 April 2017, https://clinicaltrials.gov/ct2/show/study/NCT03116412
|
|
| 8. |
- Attauabi, Mohamed, et al.
(författare)
-
Influence of Genetics, Immunity and the Microbiome on the Prognosis of Inflammatory Bowel Disease (IBD Prognosis Study) : the protocol for a Copenhagen IBD Inception Cohort Study
- 2022
-
Ingår i: BMJ Open. - : BMJ Publishing Group Ltd. - 2044-6055. ; 12:6, s. e055779-e055779
-
Tidskriftsartikel (refereegranskat)abstract
- Introduction: Inflammatory bowel diseases (IBD), encompassing Crohn's disease and ulcerative colitis, are chronic, inflammatory diseases of the gastrointestinal tract. We have initiated a Danish population-based inception cohort study aiming to investigate the underlying mechanisms for the heterogeneous course of IBD, including need for, and response to, treatment.Methods and analysis: IBD Prognosis Study is a prospective, population-based inception cohort study of unselected, newly diagnosed adult, adolescent and paediatric patients with IBD within the uptake area of Hvidovre University Hospital and Herlev University Hospital, Denmark, which covers approximately 1 050 000 inhabitants (~20% of the Danish population). The diagnosis of IBD will be according to the Porto diagnostic criteria in paediatric and adolescent patients or the Copenhagen diagnostic criteria in adult patients. All patients will be followed prospectively with regular clinical examinations including ileocolonoscopies, MRI of the small intestine, validated patient-reported measures and objective examinations with intestinal ultrasound. In addition, intestinal biopsies from ileocolonoscopies, stool, rectal swabs, saliva samples, swabs of the oral cavity and blood samples will be collected systematically for the analysis of biomarkers, microbiome and genetic profiles. Environmental factors and quality of life will be assessed using questionnaires and, when available, automatic registration of purchase data. The occurrence and course of extraintestinal manifestations will be evaluated by rheumatologists, dermatologists and dentists, and assessed by MR cholangiopancreatography, MR of the spine and sacroiliac joints, ultrasonography of peripheral joints and entheses, clinical oral examination, as well as panoramic radiograph of the jaws. Fibroscans and dual-energy X-ray absorptiometry scans will be performed to monitor occurrence and course of chronic liver diseases, osteopenia and osteoporosis.Ethics and dissemination: This study has been approved by Ethics Committee of the Capital Region of Denmark (approval number: H-20065831). Study results will be disseminated through publication in international scientific journals and presentation at (inter)national conferences.
|
|
| 9. |
- Clemente, Francesco, et al.
(författare)
-
Touch and Hearing Mediate Osseoperception
- 2017
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 7
-
Tidskriftsartikel (refereegranskat)abstract
- Osseoperception is the sensation arising from the mechanical stimulation of a bone-anchored prosthesis. Here we show that not only touch, but also hearing is involved in this phenomenon. Using mechanical vibrations ranging from 0.1 to 6 kHz, we performed four psychophysical measures (perception threshold, sensation discrimination, frequency discrimination and reaction time) on 12 upper and lower limb amputees and found that subjects: consistently reported perceiving a sound when the stimulus was delivered at frequencies equal to or above 400 Hz; were able to discriminate frequency differences between stimuli delivered at high stimulation frequencies (similar to 1500 Hz); improved their reaction time for bimodal stimuli (i.e. when both vibration and sound were perceived). Our results demonstrate that osseoperception is a multisensory perception, which can explain the improved environment perception of bone-anchored prosthesis users. This phenomenon might be exploited in novel prosthetic devices to enhance their control, thus ultimately improving the amputees' quality of life.
|
|
| 10. |
- Isaksson-Daun, Johan, et al.
(författare)
-
Using Portable Virtual Reality to Assess Mobility of Blind and Low-Vision Individuals With the Audomni Sensory Supplementation Feedback
- 2024
-
Ingår i: IEEE Access. - 2169-3536. ; 12
-
Tidskriftsartikel (refereegranskat)abstract
- Numerous electronic travel aids (ETAs) to increase the mobility of blind or low-vision (BLV) individuals have been proposed. However, the lack of established and well-motivated methods, and of recruiting enough BLV test participants, keeps a successful aid illusory. To combat this, a new aid-agnostic questionnaire focused on mobility, the Desire of Use Questionnaire for Mobility of BLV individuals (DoUQ-MoB) and a new portable, large-scale-exploration virtual reality (VR) system, the Parrot-VR, were employed to evaluate the ETA Audomni. Through VR and Audomni, 19 heterogenous BLV participants traversed large-scale urban environments. Their experiences were probed through the DoUQ-MoB, and their movement analyzed. Numerous results are presented, a highlight being that most participants, 76 %, responded that it was very or extremely likely that they would want to use Audomni along with their current aid. Further, Parrot-VR assists in recruiting a satisfying number of diverse BLV participants; and DoUQ-MoB allows to systematically probe their opinions of an aid, and how it relates to others aids, in a considerable quantity of mobility aid aspects. This work illuminates some shortcomings of Audomni, but also shows a majority of BLV participants actually wanting to use a proposed ETA — a result rarely seen so distinctly in the field, and which encourages the continuing efforts of the project. The results are supported by a novel test procedure, which might serve as future inspiration to the field.
|
|
