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  • 301.
    Ahlner, Johan
    et al.
    Linköping University, Department of Medicine and Health Sciences, Clinical Pharmacology . Linköping University, Faculty of Health Sciences.
    Aamo, T. O.
    Trondheims University.
    THERAPEUTIC DRUG MONITORING AND CLINICAL TOXICOLOGY2009In: in BASIC & CLINICAL PHARMACOLOGY & TOXICOLOGY, vol 105, 2009, Vol. 105, p. 16-16Conference paper (Refereed)
    Abstract [en]

    n/a

  • 302.
    Ahlner, Johan
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Pharmacology.
    Druid, H
    Holmgren, P
    Genotyping avseende metabolism av läkemedel och droger - betydelse i forensiska sammanhang.1999In: Nordisk Rettsmedisin, ISSN 0809-1498, Vol. 5, p. 47-48Article in journal (Other (popular science, discussion, etc.))
  • 303.
    Ahlner, Johan
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Swedish National Board Forens Med, Department Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Holmgren, Anita
    Swedish National Board Forens Med, Department Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Jones, A Wayne
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Swedish National Board Forens Med, Department Forens Genet and Forens Toxicol, Linkoping, Sweden.
    Demographics and post-mortem toxicology findings in deaths among people arrested multiple times for use of illicit drugs and/or impaired driving2016In: Forensic Science International, ISSN 0379-0738, E-ISSN 1872-6283, Vol. 265, p. 138-143Article in journal (Refereed)
    Abstract [en]

    Background: Multiple arrests for use of illicit drugs and/or impaired driving strongly suggests the existence of a personality disorder and/or a substance abuse problem. Methods: This retrospective study (1993-2010) used a national forensic toxicology database (TOXBASE), and we identified 3943 individuals with two or more arrests for use of illicit drugs and/or impaired driving. These individuals had subsequently died from a fatal drug poisoning or some other cause of death, such as trauma. Results: Of the 3943 repeat offenders 1807 (46%) died from a fatal drug overdose and 2136 (54%) died from other causes (p amp;lt; 0.001). The repeat offenders were predominantly male (90% vs 10%) and mean age of drug poisoning deaths was 5 y younger (mean 35 y) than other causes of death (mean 40 y). Significantly more repeat offenders (46%) died from drug overdose compared with all other forensic autopsies (14%) (p amp;lt; 0.001). Four or more drugs were identified in femoral blood in 44% of deaths from poisoning (drug overdose) compared with 18% of deaths by other causes (p amp;lt; 0.001). The manner of death was considered accidental in 54% of deaths among repeat offenders compared with 28% for other suspicious deaths (p amp;lt; 0.001). The psychoactive substances most commonly identified in autopsy blood from repeat offenders were ethanol, morphine (from heroin), diazepam, amphetamines, cannabis, and various opioids. Conclusions: This study shows that people arrested multiple times for use of illicit drugs and/or impaired driving are more likely to die by accidentally overdosing with drugs. Lives might be saved if repeat offenders were sentenced to treatment and rehabilitation for their drug abuse problem instead of conventional penalties for drug-related crimes. (C) 2016 Elsevier Ireland Ltd. All rights reserved.

  • 304.
    Ahlner, Johan
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Holmgren, Anita
    National Board for Forensic Medicine, Linkoping, Sweden .
    Jones, A Wayne
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Health Sciences.
    Prevalence of alcohol and other drugs and the concentrations in blood of drivers killed in road traffic crashes in Sweden2014In: Scandinavian Journal of Public Health, ISSN 1403-4948, E-ISSN 1651-1905, Vol. 42, no 2, p. 177-183Article in journal (Refereed)
    Abstract [en]

    Background: Drunk or drug-impaired drivers represent a major public health and societal problem worldwide. Because over 95% of drivers killed on the roads in Sweden are autopsied, reliable information is available about the use of alcohol and/or other drug before the crash. Methods: This retrospective 4-year study (2008-2011) used a forensic toxicology database (TOXBASE) to evaluate the concentrations of alcohol and other drugs in blood samples from drivers killed in road-traffic crashes. Results: The mean age of all victims (N = 895) was 48 +/- 20 years, and the majority were male (86%). In 504 drivers (56%), the results of toxicological analysis were negative and these victims were older; mean age (+/- SD) 47 +/- 20 years, than alcohol positive cases (35 +/- 14 years) and illicit drug users (34 +/- 15 years). In 21% of fatalities, blood-alcohol concentration (BAC) was above the statutory limit for driving (0.2 g/L), although the median BAC was appreciably higher (1.72 g/L). Illicit drugs (mainly amphetamine and cannabis) were identified in similar to 7% of victims, either alone (2.5%), together with alcohol (1.8%) or a prescription drug (2%). The psychoactive prescription drugs identified were mainly benzodiazepines, z-hypnotics and tramadol, which were found in the blood of 7.6% of crash victims. Conclusions: The high median BAC in fatally-injured drivers speaks strongly towards alcohol-induced impairment as being responsible for the crash. Compared with alcohol, the prevalence of illicit and psychoactive prescription drugs was fairly low despite a dramatic increase in the number of drug-impaired drivers arrested by the police after a zero-tolerance law was introduced in 1999.

  • 305.
    Ahlner, Johan
    et al.
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Zackrisson, Anna Lena
    Linköping University, Department of Medical and Health Sciences, Clinical Pharmacology. Linköping University, Faculty of Health Sciences.
    Lindblom, Bertil
    Linköping University, Department of Clinical and Experimental Medicine, Forensic Genetics. Linköping University, Faculty of Health Sciences.
    Bertilsson, Leif
    Karolinska Institute.
    Editorial Material: CYP2D6, serotonin and suicide2010In: Pharmacogenomics (London), ISSN 1462-2416, E-ISSN 1744-8042, Vol. 11, no 7, p. 903-905Article in journal (Other academic)
    Abstract [en]

    n/a

  • 306.
    Ahlqvist-Rastad, Jane
    et al.
    Medical Products Agency, Uppsala, Sweden.
    Albertsson, Maria
    Karolinska University Hospital, Stockholm, Sweden.
    Bergh, Jonas
    Karolinska University Hospital, Stockholm, Sweden.
    Birgegård, Gunnar
    Uppsala University Hospital, Uppsala, Sweden.
    Johansson, Peter
    Sahlgrenska University Hospital, Gothenborg, Sweden.
    Jonsson, Bertil
    Medical Products Agency, Uppsala, Sweden.
    Kjellen, Elisabeth
    Lund University Hospital, Sweden.
    Påhlman, Sven
    Malmö University Hospital MAS, Sweden.
    Zackrisson, Björn
    University Hospital of Northern Sweden, Umeå, Sweden.
    Österborg, Anders
    Karolinska University Hospital, Stockholm, Sweden.
    Erythropoietin therapy and cancer related anaemia: updated Swedish recommendations2007In: Medical Oncology, ISSN 1357-0560, E-ISSN 1559-131X, Vol. 24, no 3, p. 267-272Article in journal (Refereed)
    Abstract [en]

    Due to concerns related to treatment with erythropoietin (EPO) and possible negative effects on tumour control, a workshop was organised by the Medical Products Agency of Sweden with the aim to revise national treatment guidelines if needed. In patients with solid tumours, conflicting results have been reported with respect to tumour control and survival. Until further notice it is therefore recommended that EPO should be used restrictively in the treatment of patients with cancer and that the anticipated improvement in quality of life should be evaluated against potential risks.

  • 307.
    Ahlsson, Anders
    et al.
    Örebro University Hospital.
    Jideus, Lena
    Uppsala University Hospital .
    Albåge, Anders
    Karolinska University Hospital, Stockholm.
    Källner, Göran
    Karolinska University Hospital, Stockholm.
    Holmgren, Anders
    Umeå University Hospital .
    Boano, Gabriella
    Östergötlands Läns Landsting.
    Hermansson, Ulf
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Kimblad, Per-Ola
    Lund University Hospital.
    Schersten, Henrik
    Sahlgrenska University Hospital, Gothenburg.
    Sjögren, Johan
    Lund University Hospital .
    Ståhle, Elisabeth
    Uppsala University Hospital.
    Åberg, Bengt
    Blekinge Hospital, Karskrona, Sahlgrenska University Hospital, Gothenburg.
    Berglin, Eva
    Sahlgrenska University Hospital, Gothenburg.
    A Swedish consensus on the surgical treatment of concomitant atrial fibrillation2012In: Scandinavian Cardiovascular Journal, ISSN 1401-7431, E-ISSN 1651-2006, Vol. 46, no 4, p. 212-218Article, review/survey (Refereed)
    Abstract [en]

    Atrial fibrillation (AF) is a common arrhythmia among patients scheduled for open heart surgery and is associated with increased morbidity and mortality. According to international guidelines, symptomatic and selected asymptomatic patients should be offered concomitant surgical AF ablation in conjunction with valvular or coronary surgery. The gold standard in AF surgery is the Cox Maze III ("cut-and-sew") procedure, with surgical incisions in both atria according to a specified pattern, in order to prevent AF reentry circuits from developing. Over 90% of patients treated with the Cox Maze III procedure are free of AF after 1 year. Recent developments in ablation technology have introduced several energy sources capable of creating nonconducting atrial wall lesions. In addition, simplified lesion patterns have been suggested, but results with these techniques have been unsatisfactory. There is a clear need for standardization in AF surgery. The Swedish Arrhythmia Surgery Group, represented by surgeons from all Swedish units for cardiothoracic surgery, has therefore reached a consensus on surgical treatment of concomitant AF. This consensus emphasizes adherence to the lesion pattern in the Cox Maze III procedure and the use of biatrial lesions in nonparoxysmal AF.

  • 308.
    Ahlstrand, I
    et al.
    Jönköping University.
    Thyberg, Ingrid
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Falkmer, T
    Curtin University, Perth, Australia.
    Björk, M
    OP0209-HPR Less Pain and Activity Limitations in Today's Early RA Patients Compared with Patients Diagnosed 10 Years Earlier (The Swedish Tira-Project)2014Conference paper (Refereed)
    Abstract [en]

    Background: Over the last decades the RA-treatment strategies have changed considerably. Routines for early RA diagnosis and instituted disease modifying anti rheumatic drugs (DMARDs) have been established. In the early 2000s biologic agents also became available for treatment purposes. Despite these altered and improved strategies RA patients continue to report pain and activity limitations; women more so than men.Objectives: To study differences regarding pain and activity limitations during the first three years after diagnosis of RA in today's patients compared with patients diagnosed 10 years earlier from a gender perspective.Methods: This study was based on patients recruited to the project “early interventions in RA” (TIRA). In the first cohort (TIRA-1) 320 patients were included during 1996-1998. In the second cohort (TIRA-2) 463 patients were included during 2006-2008. Disease activity score 28 joint count (DAS-28) and medication were registered. Pain intensity (VAS), bodily pain (BP) in Short Form36 (SF-36) and activity limitation (Health Assessment Questionnaire, HAQ) were reported at inclusion and at follow-ups after one, two and three years.Results: Disease activity did not differ between cohorts at inclusion, but was significant lower at the follow ups in the TIRA-2 cohort compared with the TIRA-1 cohort. Patients in TIRA2 were prescribed traditional DMARD:s and biologic agents more frequent than in TIRA-1. The TIRA-2 patients reported significantly higher pain intensity and activity limitations at inclusion but lower pain intensity and activity limitations at all follow-ups than TIRA-1 patients. There were no significant differences between cohorts regarding bodily pain at inclusion, but thereafter the TIRA-2 patients showed significant lower bodily pain than the TIRA-1 patients. Men reported lower activity limitation than women in TIRA-1; otherwise there were no gender differences in TIRA-1. In TIRA-2, there were no significant gender differences regarding pain at inclusion. However, men reported lower pain than women at all follow-ups. Women, in turn, reported significantly higher activity limitations at all time points in TIRA-2. Pain and activity limitations were significantly reduced from inclusion to the one year follow-up but remained stable thereafter.Conclusions: Both women and men in today's early RA patient cohort report lower pain and less activity limitations at the follow ups after diagnosis of RA compared to 10 years earlier. However, both activity limitations and bodily pain are still pronounced.Disclosure of Interest: None declared

  • 309.
    Ahlstrand, I.
    et al.
    School of Health Sciences, Jönköping University, Jönköping, Sweden.
    Thyberg, Ingrid
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Rheumatology.
    Falkmer, Torbjörn
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Pain and Rehabilitation Center. School of Health Sciences, Jönköping University, Jönköping, Sweden; School of Occupational Therapy and Social Work, CHIRI, Curtin University, Perth, WA, Australia.
    Dahlström, Örjan
    Linköping University, Department of Behavioural Sciences and Learning, Disability Research. Linköping University, Faculty of Arts and Sciences. Linköping University, The Swedish Institute for Disability Research.
    Björk, Mathilda
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Rehabilitation Center. School of Health Sciences, Jönköping University, Jönköping, Sweden.
    Pain and activity limitations in women and men with contemporary treated early RA compared to 10 years ago: the Swedish TIRA project2015In: Scandinavian Journal of Rheumatology, ISSN 0300-9742, E-ISSN 1502-7732, Vol. 44, no 4, p. 259-264Article in journal (Refereed)
    Abstract [en]

    Objectives: To study differences regarding pain and activity limitations during the 3 years following diagnosis in women and men with contemporary treated early RA compared with their counterparts who were diagnosed 10 years earlier. Method: This study was based on patients recruited to the Early Intervention in RA (TIRA) project. In the first cohort (TIRA-1) 320 patients were included in time for diagnosis during 1996-1998 and 463 patients were included in the second cohort (TIRA-2) during 2006-2009. Disease activity, pain intensity (Visual Analogue Scale, VAS), bodily pain (BP) in the 36-item Short Form Health Survey (SF-36), activity limitations (Health Assessment Questionnaire, HAQ), and medication were reported at inclusion and at follow-up after 1, 2, and 3 years. Results: Disease activity, pain, and activity limitations were pronounced at inclusion across both genders and in both cohorts, with some improvement observed during the first year after diagnosis. Disease activity did not differ between cohorts at inclusion but was significantly lower at the follow-ups in the TIRA-2 cohort, in which the patients were prescribed traditional disease-modifying anti-rheumatic drugs (DMARDs) and biological agents more frequently. In TIRA-2, patients reported significantly lower pain and activity limitations at all follow-ups, with men reporting lower pain than women. Women reported significantly higher activity limitations at all time points in TIRA-2. Conclusions: Pain and activity limitations were still pronounced in the contemporary treated early RA cohort compared with their counterparts diagnosed 10 years earlier and both of these factors need to be addressed in clinical settings.

  • 310.
    Ahlstrand, Inger
    et al.
    ADULT, HHJ, Hälsohögskolan, Högskolan i Jönköping.
    Björk, Mathilda
    Avd. för rehabilitering, HHJ, Hälsohögskolan, Högskolan i Jönköping.
    Thyberg, Ingrid
    Linköping University, Department of Medical and Health Sciences, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Rheumatology.
    Börsbo, Björn
    Linköping University, Department of Medical and Health Sciences, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences.
    Falkmer, Torbjörn
    Linköping University, Department of Medical and Health Sciences, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Habilitation in Central County.
    Pain and daily activities in Rheumatoid Arthritis2012In: Disability and Rehabilitation, ISSN 0963-8288, E-ISSN 1464-5165, Vol. 34, no 15, p. 1245-1253Article in journal (Refereed)
    Abstract [en]

    Aim: The aim of this study was to describe experiences of pain and its relationship to daily activities in people with rheumatoid arthritis (RA). Method: Seven semi-structured focus group discussions were conducted with 33 men and women of different ages with RA. Data were analysed with content analysis. Results: Pain affected everyday life and may be a barrier to perform valued activities. Regarding the impact of pain on participation and independence, personal factors and the social environment were found to be important. It could be a struggle to find the right activity balance, since it was easy to be overactive, triggering subsequent elevation of pain levels. However, the participants also described activities as a mediator of pain and a distraction from it. Conclusion: The relationship between pain and daily activities in RA was complex. Pain as an impairment was expressed to be related to activity limitations and participation restrictions, as well as to contextual factors. These findings highlight the clinical importance of paying attention to the complexity of pain and its relation to daily activities and participation.

  • 311.
    Ahlstrand, Inger
    et al.
    Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för rehabilitering.
    Björk, Mathilda
    Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för rehabilitering.
    Thyberg, Ingrid
    Linköping University, Department of Clinical and Experimental Medicine, Rheumatology. Linköping University, Faculty of Health Sciences.
    Börsbo, Björn
    Linköping University, Department of Clinical and Experimental Medicine, Rehabilitation Medicine. Linköping University, Faculty of Health Sciences.
    Falkmer, Torbjörn
    Hälsohögskolan, Högskolan i Jönköping, HHJ, Avd. för rehabilitering.
    Smärta och dagliga aktiviteter vid Reumatoid artrit ur ett patientperspektiv2011Conference paper (Other academic)
    Abstract [sv]

    Bakgrund: Smärta vid Reumatoid artrit (RA) ärett välkänt symtom som orsakar lidande ochaktivitetsbegränsning. Traditionellt mäts smärtainom reumatologin som smärtintensitet på enVisuell Analog Skala (VAS). Kunskapen kring hurpatienter med RA upplever smärta och dess konsekvenser är begränsad. Patientens egenbeskrivning behövs som underlag för behandlingsplanering och för att utveckla nya metoderför att beskriva problematiken.Syfte: Syftet med studien är att beskriva smärtavid RA ur ett patientperspektiv med fokus på hursmärtan påverkar dagliga aktiviteter.Metod: Patienter med diagnostiserad RA i syd-östra Sverige identifierades via Svenska Reumatologiregistret. Urvalet baserades på minst 5 årssjukdomsduration och minst 40 mm smärtintensitet på VAS vid de två senaste besöken på reumatologklinik. Sammanlagt 33 patienter, 7 män och26 kvinnor, deltog i sju fokusgrupper. Gruppernaformades utifrån kön och ålder. Intervjuguideninnehöll frågor som: Hur beskriver patienter medRA sin smärta? Vad påverkar smärtan? Vilkakonsekvenser har smärtan för aktivitetsutförande,aktivitetsbalans och undvikande av aktivitet? Enkvalitativ innehållsanalys görs.Resultat/förväntat resultat: Analyser hittills visar patienternas frustration över att inteklara det man vill eller behöver göra, beroendeav andra, minskade möjligheter till delaktigheti sociala sammanhang. Och närståendes betydelse. Analyserna visar att smärtan är relaterad till Göteborg6-8 april 201134trötthet, stress och sinnesstämning och att arbeteeller andra aktiviteter medverkar till att glömmabort smärtan och uppehålla förmåga. Analysenslutförs under hösten.Konklusion: Denna studie förväntas genererany angelägen kunskap om och förståelse försmärta.

  • 312.
    Ahlstrand, Inger
    et al.
    Jonköping University, Sweden.
    Björk, Mathilda
    Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Rehabilitation Center. Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Jonköping University, Sweden.
    Thyberg, Ingrid
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Rheumatology.
    Falkmer, Torbjörn
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Pain and Rehabilitation Center. Jonköping University, Sweden; Curtin University, Australia.
    Pain and difficulties performing valued life activities in women and men with rheumatoid arthritis2015In: Clinical Rheumatology, ISSN 0770-3198, E-ISSN 1434-9949, Vol. 34, no 8, p. 1353-1362Article in journal (Refereed)
    Abstract [en]

    This study aimed to examine the difficulties with performing valued life activities in relation to pain intensity in women and men with rheumatoid arthritis (RA). In total, 737 persons with RA (73 % women) from three rheumatology units in Sweden responded to a questionnaire measuring performance of 33 valued life activities and self-rated pain. The relationships between performance of valued life activities (VLAs) and pain (measured by visual analogue scale (VAS)) were analysed based on gender. Multiple linear regression analyses were conducted with the total VLA score as dependent variable. Women reported more pain and difficulties in performing valued life activities than men. Across genders, 85 % reported at least one valued life activity affected by RA. Significantly more women than men encountered difficulties in performing some activities such as cooking, gardening and meeting new people. Women reported higher pain intensity (35 mm) than men (31 mm). Almost all 33 difficulty ratings for valued life activities were higher among persons with high pain (greater than 40 mm) than persons with lower pain. Difficulty ratings for valued life activities correlated positively with pain in persons with lower pain, but not among those with high pain. The results highlight the importance of addressing pain, especially among women with RA, as they reported pain to impact on their valued life activities. Interestingly, this was evident also in women with lower levels of pain.

  • 313.
    Ahlstrand, Inger
    et al.
    School of Health and Welfare, Jönköping University, Jönköping, Sweden.
    Vaz, Sharmila
    School of Occupational Therapy & Social Work, CHIRI, Curtin University, Perth, WA, Australia.
    Falkmer, Torbjörn
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Pain and Rehabilitation Center. School of Health and Welfare, Jönköping University, Jönköping, Sweden.
    Thyberg, Ingrid
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Rheumatology.
    Björk, Mathilda
    Linköping University, Department of Social and Welfare Studies, Division of Occupational Therapy. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Rheumatology.
    Self-efficacy and pain acceptance as mediators of the relationship between pain and performance of valued life activities in women and men with rheumatoid arthritis2017In: Clinical Rehabilitation, ISSN 0269-2155, E-ISSN 1477-0873, Vol. 31, no 6, p. 824-834Article in journal (Refereed)
    Abstract [en]

    OBJECTIVE: To study whether personal factors (self-efficacy and pain acceptance) mediate the relationship between pain and performance of valued life activities in persons with rheumatoid arthritis.

    METHODS: Persons with rheumatoid arthritis for at least four years (n = 737; 73% women) answered a questionnaire measuring self-efficacy, pain acceptance, performance of valued life activities, and self-rated pain. Relationships among these constructs were explored using univariate and multivariate analyses. Structural equation modelling was then used to examine the mediational role of personal factors on the relationship between pain and performance of valued life activities.

    RESULTS: A direct negative association between pain and performance of valued life activities was identified (Beta = .34, P < .001). This suggests that people with rheumatoid arthritis who had higher levels of pain has increased difficulties in performing valued life activities. Self-efficacy and activity engagement component of pain acceptance mediated the relationship between pain and performance of valued life activities, however the pain willingness component of pain acceptance did not influence participation in valued life activities.

    CONCLUSION: These findings highlight the importance of considering personal factors, such as pain acceptance and self-efficacy, in facilitating participation in valued life activities.

  • 314.
    Ahlstrom, Christer
    et al.
    Swedish Natl Rd and Transport Res Inst VTI, Linkoping, Sweden.
    Lovgren, Maria Gink
    Volvo Bus Corp, Denmark.
    Nilsson, Mats
    Volvo Bus Corp, Denmark.
    Willstrand, Tania Dukic
    Swedish Natl Rd and Transport Res Inst VTI, Linkoping, Sweden.
    Anund, Anna
    Not Found:Linkoping Univ, Rehabil Med, Linkoping, Sweden; Swedish Natl Rd and Transport Res Inst VTI, Linkoping, Sweden.
    The effect of an active steering system on city bus drivers muscle activity2019In: International Journal of Occupational Safety and Ergonomics, ISSN 1080-3548, E-ISSN 2376-9130, Vol. 25, no 3, p. 377-385Article in journal (Refereed)
    Abstract [en]

    City bus drivers spend hours driving under time pressure, in congested traffic and in a monotonous sitting position. This leads to unhealthy working conditions, especially in terms of physical and psychological stress. The aim of this study is to investigate whether an active steering system can alleviate the musculoskeletal stress involved in manoeuvring a bus. Twenty bus drivers drove a city bus equipped with the Volvo dynamic steering (VDS) support system in real traffic. Steering effort was evaluated with electromyography and with a questionnaire. Compared to baseline, VDS significantly reduced the required muscle activity by on average 15-25% while turning, and up to 68% in the part of the manoeuvre requiring maximum effort. The bus drivers believed that VDS will help reduce neck and shoulder problems, and they expressed a desire to have VDS installed in their own bus.

  • 315.
    Ahlstrom, Christina A.
    et al.
    US Geol Survey, AK 99508 USA.
    Bonnedahl, Jonas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Kalmar Cty Hosp, Sweden.
    Woksepp, Hanna
    Kalmar Cty Hosp, Sweden.
    Hernandez, Jorge
    Uppsala Univ, Sweden.
    Olsen, Bjorn
    Uppsala Univ, Sweden.
    Ramey, Andrew M.
    US Geol Survey, AK 99508 USA.
    Acquisition and dissemination of cephalosporin-resistant E.coli in migratory birds sampled at an Alaska landfill as inferred through genomic analysis2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 7361Article in journal (Refereed)
    Abstract [en]

    Antimicrobial resistance (AMR) in bacterial pathogens threatens global health, though the spread of AMR bacteria and AMR genes between humans, animals, and the environment is still largely unknown. Here, we investigated the role of wild birds in the epidemiology of AMR Escherichia coli. Using next-generation sequencing, we characterized cephalosporin-resistant E. coli cultured from sympatric gulls and bald eagles inhabiting a landfill habitat in Alaska to identify genetic determinants conferring AMR, explore potential transmission pathways of AMR bacteria and genes at this site, and investigate how their genetic diversity compares to isolates reported in other taxa. We found genetically diverse E. coli isolates with sequence types previously associated with human infections and resistance genes of clinical importance, including blaCTX-M and blaCMY. Identical resistance profiles were observed in genetically unrelated E. coli isolates from both gulls and bald eagles. Conversely, isolates with indistinguishable core-genomes were found to have different resistance profiles. Our findings support complex epidemiological interactions including bacterial strain sharing between gulls and bald eagles and horizontal gene transfer among E. coli harboured by birds. Results suggest that landfills may serve as a source for AMR acquisition and/or maintenance, including bacterial sequence types and AMR genes relevant to human health.

  • 316.
    Ahlstrom, G.
    et al.
    Ahlström, G., Department of Health Sciences, University of Örebro, SE-701 82 Örebro, Sweden.
    Lindvall, Björn
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Neurology . Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Neurology.
    Wenneberg, S.
    Department of Health Sciences, University of Örebro, SE-701 82 Örebro, Sweden.
    Gunnarsson, L.G.
    Department of Neurology and Neurophysiology, Örebro University Hospital, Örebro, Sweden.
    A comprehensive rehabilitation programme tailored to the needs of adults with muscular dystrophy2006In: Clinical Rehabilitation, ISSN 0269-2155, E-ISSN 1477-0873, Vol. 20, no 2, p. 132-141Article in journal (Refereed)
    Abstract [en]

    Objective: To assess if activities of daily living (ADL), coping and quality of life could be improved in adults with muscular dystrophy through a comprehensive rehabilitation programme. Design: Quasi-experimental, controlled clinical study comparing patients with similar age and disease aspects. Setting: Two different counties in Sweden, being either study or control setting. Subjects: The study group comprised 37 adults (21 women, 16 men, mean age 50 years), while the control group comprised 39 people (25 women, 14 men, mean age 46 years). Interventions: Four rehabilitation sessions tailored to different medical, physical and psychosocial needs of the patients, comprising a total of 10 days over a period of 18 months. Main measures: ADL, the Mental Adjustment to Cancer Scale measuring coping strategies, the Sickness Impact Profile measuring health-related quality of life, the Hospital Anxiety and Depression Scale, and the Psychosocial Well-being Questionnaire. Results: No significant differences were found between groups with regard to the outcome measures. There was increased dependence on others in ADL after 18 months in both groups, but it was more pronounced in the control group. Furthermore, a clear trend was observed in the data with regard to coping patterns, the control group using more coping strategies such as 'Helplessness/hopelessness' (P = 0.057), 'Anxious preoccupation' (P = 0.085) and 'Fatalistic' (P = 0.073) when being compared to the study group. Conclusions: No apparent effects on ADL were found from the rehabilitation programme, although there was a tendency of reduction of maladaptive coping patterns in the study group. This initial study may provide the rationale and basis for a randomized controlled trial. © 2006 Edward Arnold (Publishers) Ltd.

  • 317.
    Ahlstrom, Gerd
    et al.
    Lund Univ, Sweden.
    Nilsen, Per
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Benzein, Eva
    Linnaeus Univ, Sweden.
    Behm, Lina
    Lund Univ, Sweden.
    Wallerstedt, Birgitta
    Linnaeus Univ, Sweden.
    Persson, Magnus
    Lund Univ, Sweden.
    Sandgren, Anna
    Linnaeus Univ, Sweden.
    Implementation of knowledge-based palliative care in nursing homes and pre-post post evaluation by cross-over design: a study protocol2018In: BMC Palliative Care, ISSN 1472-684X, E-ISSN 1472-684X, Vol. 17, article id 52Article in journal (Refereed)
    Abstract [en]

    Background: The demography of the world is changing as the population is ageing. Because of this change to a higher proportion of older people, the WHO has called for improved palliative care for older persons. A large number of all deaths in the industrialised world occur while older people are living in nursing homes and therefore a key question becomes how the principles of palliative care can be implemented in that context. The aims of this study are: a) to describe a model of an educational intervention with the goal of implementing knowledge-based palliative care in nursing homes, and b) to describe the design of the evaluation of the effectiveness regarding the implementation of knowledge-based palliative care. Methods/design: A complex intervention is evaluated by means of a cross-over design. An educational intervention concerning palliative care consisting of five seminars during 6 months for staff and managers has been developed and conducted in 20 nursing homes in two counties. Before the intervention started, the feasibility was tested in a pilot study conducted in nursing homes not included in the main study. The intervention is evaluated through a non-randomized experimental design with intervention and control groups and pre- and post-assessments. The evaluation includes older persons living in nursing homes, next-of-kin, staff and managers. Data collection consists of quantitative methods such as questionnaires and register data and qualitative methods in the form of individual interviews, focus-group interviews and participant observations. Discussion: The research will contribute to new knowledge about how to implement knowledge-based palliative care in a nursing home setting. A strength of this project is that the Medical Research Council framework of complex intervention is applied. The four recommended stages, Development, Feasibility and piloting, Evaluation and Implementation, are combined for the educational intervention, which functions as a strategy to achieve knowledge-based palliative care in the nursing homes. Implementation is always a question of change and a good theoretical understanding is needed for drawing valid conclusions about the causal mechanisms of change. The topic is highly relevant considering the worlds ageing population. The data collection is completed and the analysis is ongoing.

  • 318.
    Ahlström, Christer
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Processing of the Phonocardiographic Signal: methods for the intelligent stethoscope2006Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Phonocardiographic signals contain bioacoustic information reflecting the operation of the heart. Normally there are two heart sounds, and additional sounds indicate disease. If a third heart sound is present it could be a sign of heart failure whereas a murmur indicates defective valves or an orifice in the septal wall. The primary aim of this thesis is to use signal processing tools to improve the diagnostic value of this information. More specifically, three different methods have been developed:

    • A nonlinear change detection method has been applied to automatically detect heart sounds. The first and the second heart sounds can be found using recurrence times of the first kind while the third heart sound can be found using recurrence times of the second kind. Most third heart sound occurrences were detected (98 %), but the amount of false extra detections was rather high (7 % of the heart cycles).

    • Heart sounds obscure the interpretation of lung sounds. A new method based on nonlinear prediction has been developed to remove this undesired disturbance. High similarity was obtained when comparing actual lung sounds with lung sounds after removal of heart sounds.

    • Analysis methods such as Shannon energy, wavelets and recurrence quantification analysis were used to extract information from the phonocardiographic signal. The most prominent features, determined by a feature selection method, were used to create a new feature set for heart murmur classification. The classification result was 86 % when separating patients with aortic stenosis, mitral insufficiency and physiological murmurs.

    The derived methods give reasonable results, and they all provide a step forward in the quest for an intelligent stethoscope, a universal phonocardiography tool able to enhance auscultation by improving sound quality, emphasizing abnormal events in the heart cycle and distinguishing different heart murmurs.

    List of papers
    1. Heart sound cancellation from lung sound recordings using recurrence time statistics and nonlinear prediction
    Open this publication in new window or tab >>Heart sound cancellation from lung sound recordings using recurrence time statistics and nonlinear prediction
    2005 (English)In: IEEE Signal Processing Letters, ISSN 1070-9908, E-ISSN 1558-2361, Vol. 12, no 12, p. 812-815Article in journal (Refereed) Published
    Abstract [en]

    Heart sounds (HS) obscure the interpretation of lung sounds (LS). This letter presents a new method to detect and remove this undesired disturbance. The HS detection algorithm is based on a recurrence time statistic that is sensitive to changes in a reconstructed state space. Signal segments that are found to contain HS are removed, and the arising missing parts are replaced with predicted LS using a nonlinear prediction scheme. The prediction operates in the reconstructed state space and uses an iterated integrated nearest trajectory algorithm. The HS detection algorithm detects HS with an error rate of 4% false positives and 8% false negatives. The spectral difference between the reconstructed LS signal and an LS signal with removed HS was 0.34/spl plusmn/0.25, 0.50/spl plusmn/0.33, 0.46/spl plusmn/0.35, and 0.94/spl plusmn/0.64 dB/Hz in the frequency bands 20-40, 40-70, 70-150, and 150-300 Hz, respectively. The cross-correlation index was found to be 99.7%, indicating excellent similarity between actual LS and predicted LS. Listening tests performed by a skilled physician showed high-quality auditory results.

    Place, publisher, year, edition, pages
    Institutionen för medicinsk teknik, 2005
    Keywords
    Bioacoustics, heart sound (HS), lung sound (LS), nonlinear prediction, recurrence time statistics
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-11857 (URN)10.1109/LSP.2005.859528 (DOI)
    Note
    Original publication: Ahlstrom, C., Liljefeldt, O., Hult, P. and Ask, P., Heart sound cancellation from lung sound recordings using recurrence time statistics and nonlinear prediction, 2005, IEEE Signal Processing Letters, (12), 12, 812-815. http://dx.doi.org/10.1109/LSP.2005.859528. Copyright: IEEE, http://ieeexplore.ieee.org/xpl/RecentIssue.jsp?punumber=97Available from: 2008-05-20 Created: 2008-05-20 Last updated: 2017-12-13
    2. Detection of the 3rd Heart Sound using Recurrence Time Statistics
    Open this publication in new window or tab >>Detection of the 3rd Heart Sound using Recurrence Time Statistics
    2006 (English)In: Proc. 31st IEEE Int. Conf. on Acoustics, Speech and Signal Processing, Toulouse, France, 2006, 2006, p. 1040-1043Conference paper, Published paper (Other academic)
    Abstract [en]

    The 3rd heart sound (S3) is normally heard during auscultation of younger individuals, but it is also common in many patients with heart failure. Compared to the 1st and 2nd heart sounds, S3 has low amplitude and low frequency content, making it hard to detect (both manually for the physician and automatically by a detection algorithm). We present an algorithm based on a recurrence time statistic which is sensitive to changes in a reconstructed state space, particularly for detection of transitions with very low energy. Heart sound signals from ten children were used in this study. Most S3 occurrences were detected (98 %), but the amount of false extra detections was rather high (7% of the heart cycles). In conclusion, the method seems capable of detecting S3 with high accuracy and robustness.

    Series
    IEEE International Conference on Acoustics, Speech and Signal Processing. Proceedings, ISSN 1520-6149
    Keywords
    acoustic, signal detection, bioacoustics, signal reconstruction, statistics, heart sound, auscultation, heart failure, reconstructed state space, recurrence time statistics
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-14058 (URN)
    Available from: 2006-10-09 Created: 2006-10-09 Last updated: 2009-04-21
    3. Feature Extraction for Systolic Heart Murmur Classification
    Open this publication in new window or tab >>Feature Extraction for Systolic Heart Murmur Classification
    Show others...
    2006 (English)In: Annals of Biomedical Engineering, ISSN 0090-6964, E-ISSN 1573-9686, Vol. 34, no 11, p. 1666-1677Article in journal (Refereed) Published
    Abstract [en]

    Heart murmurs are often the first signs of pathological changes of the heart valves, and they are usually found during auscultation in the primary health care. Distinguishing a pathological murmur from a physiological murmur is however difficult, why an “intelligent stethoscope” with decision support abilities would be of great value. Phonocardiographic signals were acquired from 36 patients with aortic valve stenosis, mitral insufficiency or physiological murmurs, and the data were analyzed with the aim to find a suitable feature subset for automatic classification of heart murmurs. Techniques such as Shannon energy, wavelets, fractal dimensions and recurrence quantification analysis were used to extract 207 features. 157 of these features have not previously been used in heart murmur classification. A multi-domain subset consisting of 14, both old and new, features was derived using Pudil’s sequential floating forward selection (SFFS) method. This subset was compared with several single domain feature sets. Using neural network classification, the selected multi-domain subset gave the best results; 86% correct classifications compared to 68% for the first runner-up. In conclusion, the derived feature set was superior to the comparative sets, and seems rather robust to noisy data.

    Keywords
    Auscultation, Bioacoustics, Feature selection, Heart sounds, Valvular disease
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-13044 (URN)10.1007/s10439-006-9187-4 (DOI)
    Available from: 2008-03-20 Created: 2008-03-20 Last updated: 2017-12-13
  • 319.
    Ahlström, Christer
    et al.
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Rask, Peter
    University Hospital, Örebro, Sweden .
    Karlsson, Jan-Erik
    County Hospital Ryhov, Jönköping, Sweden.
    Nylander, Eva
    Linköping University, Department of Medicine and Care, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Dahlström, Ulf
    Linköping University, Department of Medicine and Care, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Hult, Peter
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Assessment of Suspected Aortic Stenosis by Auto Mutual Information Analysis of Murmurs2007In: Engineering in Medicine and Biology Society, 2007. EMBS 2007, 2007, p. 1945-1948Conference paper (Refereed)
    Abstract [en]

    Mild sclerotic thickening of the aortic valve affects 25% of the population, and the condition causes aortic valve stenosis (AS) in 2% of adults above 65 years. Echocardiography is today the clinical standard for assessing AS. However, a cost effective and uncomplicated technique that can be used for decision support in the primary health care would be of great value. In this study, recorded phonocardiographic signals were analyzed using the first local minimum of the auto mutual information (AMI) function. The AMI method measures the complexity in the sound signal, which is related to the amount of turbulence in the blood flow and thus to the severity of the stenosis. Two previously developed phonocardiographic methods for assessing AS severity were used for comparison, the murmur energy ratio and the sound spectral averaging technique. Twenty-nine patients with suspected AS were examined with Doppler echocardiography. The aortic jet velocity was used as a reference of AS severity, and it was found to correlate with the AMI method, the murmur energy ratio and the sound spectral averaging technique with the correlation coefficient R = 0.82, R = 0.73 and R = 0.76, respectively.

  • 320.
    Ahlström, Christer
    et al.
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Hult, Peter
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Detection of the 3rd Heart Sound using Recurrence Time Statistics2006In: Proc. 31st IEEE Int. Conf. on Acoustics, Speech and Signal Processing, Toulouse, France, 2006, 2006, p. 1040-1043Conference paper (Other academic)
    Abstract [en]

    The 3rd heart sound (S3) is normally heard during auscultation of younger individuals, but it is also common in many patients with heart failure. Compared to the 1st and 2nd heart sounds, S3 has low amplitude and low frequency content, making it hard to detect (both manually for the physician and automatically by a detection algorithm). We present an algorithm based on a recurrence time statistic which is sensitive to changes in a reconstructed state space, particularly for detection of transitions with very low energy. Heart sound signals from ten children were used in this study. Most S3 occurrences were detected (98 %), but the amount of false extra detections was rather high (7% of the heart cycles). In conclusion, the method seems capable of detecting S3 with high accuracy and robustness.

  • 321.
    Ahlström, Christer
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Hult, Peter
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Wheeze analysis and detection with non-linear phase-space embedding2005In: Nordic Baltic Conference Biomedical Engineering and Medical Physics,2005, Umeå: IFMBE , 2005, p. 305-Conference paper (Refereed)
  • 322.
    Ahlström, Christer
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Hult, Peter
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Rask, P
    Karlsson, J-E
    Nylander, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Dahlström, Ulf
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Cardiology. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Using the intelligent stethoscope for extraction of features for systolic heart murmur classification2006In: World Congress on Medical Physics and Biomedical Engineering WC2006,2006, 2006Conference paper (Other academic)
  • 323.
    Ahlström, Christer
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Hult, Peter
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Schmekel, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Automatisk detektering av ronki med icke-linjära metoder2004In: Svenska Läkaresällskapets riksstämma,2004, 2004, p. 66-66Conference paper (Other academic)
  • 324.
    Ahlström, Christer
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Hult, Peter
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Schmekel, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Wheeze detection with nonlinear statespace embedding2004In: International Lung Sound Association,2004, 2004, p. 38-39Conference paper (Other academic)
  • 325.
    Ahlström, Christer
    et al.
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, Faculty of Health Sciences.
    Höglund, Katja
    Hult, Peter
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, Faculty of Health Sciences.
    Häggström, Jens
    Kvart, Clarence
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, Faculty of Health Sciences.
    Assessing Aortic Stenosis using Sample Entropy of the Phonocardiographic Signal in Dogs2008In: IEEE Transactions on Biomedical Engineering, ISSN 0018-9294, E-ISSN 1558-2531, Vol. 55, no 8, p. 2107-2109Article in journal (Refereed)
    Abstract [en]

    In aortic valve stenosis (AS), heart murmurs arise as an effect of turbulent blood flow distal to the obstructed valves. With increasing AS severity, the flow becomes more unstable, and the ensuing murmur becomes more complex. We hypothesize that these hemodynamic flow changes can be quantified based on the complexity of the phonocardiographic (PCG) signal. In this study, sample entropy (SampEn) was investigated as a measure of complexity using a dog model. Twenty-seven boxer dogs with various degrees of AS were examined with Doppler echocardiography, and the peak aortic flow velocity (Vmax) was used as a reference of AS severity. SampEn correlated to Vmax with R = 0.70 using logarithmic regression. In a separate analysis, significant differences were found between physiologic murmurs and murmurs caused by AS (p < 0.05), and the area under a receiver operating characteristic curve was calculated to 0.96. Comparison with previously presented PCG measures for AS assessment showed improved performance when using SampEn, especially for differentiation between physiological murmurs and murmurs caused by mild AS. Studies in patients will be needed to properly assess the technique in humans.

  • 326.
    Ahlström, Christer
    et al.
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Höglund, Katja
    Dept. of Anatomy and Physiology, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Hult, Peter
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Häggström, Jens
    Dept. of Clinical Sciences, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Kvart, Clarence
    Dept. of Anatomy and Physiology, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Distinguishing Innocent Murmurs from Murmurs caused by Aortic Stenosis by Recurrence Quantification Analysis2006In: ROCEEDINGS OF WORLD ACADEMY OF SCIENCE, ENGINEERING AND TECHNOLOGY, VOL 18, Canakkale, Turkey: World Academy of Science, Engineering and Technology (W A S E T) , 2006, p. 40-45Conference paper (Refereed)
    Abstract [en]

    It is sometimes difficult to differentiate between innocent murmurs and pathological murmurs during auscultation. In these difficult cases, an intelligent stethoscope with decision support abilities would be of great value. In this study, using a dog model, phonocardiographic recordings were obtained from 27 boxer dogs with various degrees of aortic stenosis (AS) severity. As a reference for severity assessment, continuous wave Doppler was used. The data were analyzed with recurrence quantification analysis (RQA) with the aim to find features able to distinguish innocent murmurs from murmurs caused by AS. Four out of eight investigated RQA features showed significant differences between innocent murmurs and pathological murmurs. Using a plain linear discriminant analysis classifier, the best pair of features (recurrence rate and entropy) resulted in a sensitivity of 90% and a specificity of 88%. In conclusion, RQA provide valid features which can be used for differentiation between innocent murmurs and murmurs caused by AS.

  • 327.
    Ahlström, Christer
    et al.
    Swedish National Rd and Transport Research Institute VTI, S-58195 Linkoping, Sweden.
    Jansson, Sabina
    Linköping University, Department of Biomedical Engineering. Linköping University, Faculty of Science & Engineering.
    Anund, Anna
    Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Rehabilitation Medicine. Swedish National Rd and Transport Research Institute VTI, S-58195 Linkoping, Sweden.
    Local changes in the wake electroencephalogram precedes lane departures2017In: Journal of Sleep Research, ISSN 0962-1105, E-ISSN 1365-2869, Vol. 26, no 6, p. 816-819Article in journal (Refereed)
    Abstract [en]

    The objective of this exploratory study is to investigate if lane departures are associated with local sleep, measured via source-localized electroencephalography (EEG) theta power in the 5-9 Hz frequency range. Thirty participants drove in an advanced driving simulator, resulting in 135 lane departures at high levels of self-reported sleepiness. These lane departures were compared to matching non-departures at the same sleepiness level within the same individual. There was no correspondence between lane departures and global theta activity. However, at the local level an increased risk for lane departures was associated with increased theta content in brain regions related to motor function.

  • 328.
    Ahlström, Christer
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Johansson, Anders
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Länne, Toste
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    A respiration monitor based on electrocardiographic and photoplethysmographic sensor fusion2004In: IEEE Engineering in Medical and Biological Society,2004, Piscataway, N.J. USA: IEEEEMBS , 2004, p. 2311-Conference paper (Refereed)
  • 329.
    Ahlström, Christer
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Johansson, Anders
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Länne, Toste
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Monitorering av andning and blodtrycksförändringar baserat på EKG och hjärtljud2007In: Medicinteknik dagarna,2007, 2007Conference paper (Other academic)
  • 330.
    Ahlström, Christer
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Johansson, Anders
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Uhlin, Fredrik
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Nephrology.
    Länne, Toste
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Clinical Physiology. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Ask, Per
    Linköping University, The Institute of Technology. Linköping University, Department of Biomedical Engineering, Physiological Measurements.
    Noninvasive investigation of blood pressure changes using the pulse wave transit time: A novel approach in the monitoring of hemodialysis patients2005In: Journal of Artificial Organs, ISSN 1434-7229, E-ISSN 1619-0904, Vol. 8, no 3, p. 192-197Article in journal (Refereed)
    Abstract [en]

    Severe blood pressure changes are well known in hemodialysis. Detection and prediction of these are important for the well-being of the patient and for optimizing treatment. New noninvasive methods for this purpose are required. The pulse wave transit time technique is an indirect estimation of blood pressure, and our intention is to investigate whether this technique is applicable for hemodialysis treatment. A measurement setup utilizing lower body negative pressure and isometric contraction was used to simulate dialysis-related blood pressure changes in normal test subjects. Systolic blood pressure levels were compared to different pulse wave transit times, including and excluding the cardiac preejection period. Based on the results of these investigations, a pulse wave transit time technique adapted for dialysis treatment was developed and tried out on patients. To determine systolic blood pressure in the normal group, the total pulse wave transit time was found most suitable (including the cardiac preejection period). Correlation coefficients were r = 0.80 ± 0.06 (mean ± SD) overall and r = 0.81 ± 0.16 and r = 0.09 ± 0.62 for the hypotension and hypertension phases, respectively. When applying the adapted technique in dialysis patients, large blood pressure variations could easily be detected when present. Pulse wave transit time is correlated to systolic blood pressure within the acceptable range for a trend-indicating system. The method's applicability for dialysis treatment requires further studies. The results indicate that large sudden pressure drops, like those seen in sudden hypovolemia, can be detected. © The Japanese Society for Artificial Organs 2005.

  • 331.
    Ahlström, Christer
    et al.
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, Faculty of Health Sciences.
    Länne, Toste
    Linköping University, Department of Medicine and Health Sciences, Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Ask, Per
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, Faculty of Health Sciences.
    Johansson, Anders
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, Faculty of Health Sciences.
    A method for accurate localization of the first heart sound and possible applications2008In: Physiological Measurement, ISSN 0967-3334, E-ISSN 1361-6579, Vol. 29, no 3, p. 417-428Article in journal (Refereed)
    Abstract [en]

    We have previously developed a method for localization of the first heart sound (S1) using wavelet denoising and ECG-gated peak-picking. In this study, an additional enhancement step based on cross-correlation and ECG-gated ensemble averaging (EA) is presented. The main objective of the improved method was to localize S1 with very high temporal accuracy in (pseudo-) real time. The performance of S1 detection and localization, with and without EA enhancement, was evaluated on simulated as well as experimental data. The simulation study showed that EA enhancement reduced the localization error considerably and that S1 could be accurately localized at much lower signal-to-noise ratios. The experimental data were taken from ten healthy subjects at rest and during invoked hyper- and hypotension. For this material, the number of correct S1 detections increased from 91% to 98% when using EA enhancement. Improved performance was also demonstrated when EA enhancement was used for continuous tracking of blood pressure changes and for respiration monitoring via the electromechanical activation time. These are two typical applications where accurate localization of S1 is essential for the results.

  • 332.
    Ahlström, Gerd
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Nursing Science.
    Carlsson, C
    Att visa upp sin värld: Hur personer med stora varaktiga funktionshinder uppfattar sin livssituation relaterat till de etiska principerna i LSS2002Report (Other academic)
  • 333.
    Ahlström, Gerd
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Nursing Science.
    Wennberg, S
    Coping with illness-related problems in persons with progressive muscular diseases: the Swedish version of the Ways of Coping Questionnaire2002In: Scandinavian Journal of Caring Sciences, ISSN 0283-9318, E-ISSN 1471-6712, Vol. 16, p. 368-375Article in journal (Refereed)
  • 334. Ahlström, Monica
    et al.
    Blomé, Ulrika
    Broqvist, Mari
    Linköping University, Department of Medical and Health Sciences, Division of Health Care Analysis. Linköping University, Faculty of Medicine and Health Sciences.
    Göransson, Ingrid
    Nilsson, Anna-Karin
    Pettersson, Ulla
    Ett praktiskt försök: nationell prioriteringsmodell tillämpad i Landstinget i Kalmar Län2008Report (Other academic)
    Abstract [sv]

    Idag finns en nationell modell för hur öppna vertikala prioriteringar kan genomföras. Den är resultatet av de samlade erfarenheterna av att omsätta riksdagens riktlinjer för prioriteringar i praktiskt prioriteringsarbete. Modellen är framtagen av Socialstyrelsen, PrioriteringsCentrum samt flera vårdförbund och landsting gemensamt. Också FSA och LSR har ställt sig bakom den. Fram tills nu har det dock saknats praktisk erfarenhet av att tillämpa modellen inom arbetsterapi och sjukgymnastik. Men sedan drygt två år tillbaka har de båda rehabiliteringsenheterna Samrehab och Rehab Söder i Landstinget i Kalmar län med stöd av PrioriteringsCentrum bedrivit ett prioriteringsarbete i enlighet med modellen. Det är deras erfarenheter denna rapport handlar om.

    Prioriteringsarbetet har med nära stöd av verksamhetsledningarna letts av en projektgrupp bestående av arbetsterapeuter och sjukgymnaster från de båda enheterna som fungerat som handledare, ansvarat för metodutveckling och utbildning samt kontinuerligt utvärderat arbetet. Själva tillämpningen av den nationella modellen har ett antal utvecklingsgrupper inom olika specialistområden stått för. De har valt ut och rangordnat tillstånd och olika åtgärder som de ansett angelägna att ta fram prioriteringar för.

    Ett av syftena med prioriteringsarbetet i Samrehab och Rehab Söder var att få till stånd länsövergripande prioriteringar inom vissa verksamheter och/eller för vissa sjukdomstillstånd för en mer likvärdig vård. Idag finns elva sådana prioriteringsordningar presenterade på landstingets intranät och ytterligare ett tiotal är under bearbetning. Utöver vinsterna med det förbättrade samarbetet mellan länsdelarna har alltså den interna öppenheten i prioriteringarna ökat. Alla anställda kan lätt få fram prioriteringsordningarna via basenheternas hemsidor när man behöver det. Andra vinster av prioriteringsarbetet är att kännedomen och kunskapen om riksdagens riktlinjer för prioriteringar har ökat, att en större del av basenheternas verksamhet idag är faktabaserad än innan prioriteringsarbetet startade samt att den kliniska erfarenheten har tillvaratagits och dokumenterats på ett mer systematiskt sätt än tidigare. Det har dessutom skett en utveckling av den nationella modellen som har blivit mer konkret vad det gäller svårighetsgrad och nytta. En majoritet av deltagarna i utvecklingsgrupperna har haft en positiv inställning till att arbeta med prioriteringar utifrån modellen och upplever också att de erhållit ett språk som gör det möjligt att kommunicera prioriteringar med politiker och landstingsledning.

    I rapporten presenteras också de frågor kring modellens olika steg som dykt upp under arbetets gång. Tre frågor har dominerat; syftet med prioriteringsarbetet, tolkningen av modellen samt dokumentationen av prioriteringsarbetet.

     

    Syftet har inte alltid upplevts som helt klart och sambandet mellan prioriteringsarbetet och annat kvalitetsarbete som t ex framtagande av behandlingsriktlinjer har varit otydligt. När det gäller tolkningen av modellen har t ex graderingen av svårighetsgrad och patientnytta gett upphov till frustration. Också den skriftliga presentationen av prioriteringsordningarna har stundtals upplevts som krånglig och svår att förmedla till övriga medarbetare på ett användbart sätt.

    Alla de åtgärder som projektgruppen vidtagit för att underlätta de svårigheter som dykt upp delar de här med sig av i rapporten. Likaså pekar de ut viktiga förutsättningar för ett prioriteringsarbete (som t ex tid, kompetens, kontinuitet och legitima deltagare). Syftet med att pröva om den nationella modellen för öppna vertikala prioriteringar är användbar i Samrehabs och Rehab Söders prioriteringsarbete är uppnådd och det har inte framkommit något som ger anledning att ifrågasätta modellens grundstruktur. Förslag har dock givits bl a avseende bedömning av svårighetsgrad och patientnytta för att ytterligare underlätta tillämpningen.

    Nu planerar enheterna att gå vidare med sitt prioriteringsarbete, dels genom att fortsätta att ta fram behandlingsriktlinjer som kombineras med prioriteringar men också genom att ytterligare utveckla prioriteringsstödet för de enskilda medarbetarna i deras dagliga patientarbete. Om andra verksamheter i Sverige  följer efter detta exempel från Kalmar län med att öppet redovisa hur de hanterar prioriteringar i sin verksamhet kommer ytterligare nya erfarenheter att hjälpa metodutvecklingen på traven.

  • 335.
    Ahlvin, Anna
    et al.
    Linköping University. Region Östergötland, Public Dental Health Care.
    Warnberg Gerdin, Elisabeth
    Regional Örebro County, Sweden.
    Bågesund, Mats
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Public Dental Health Care.
    Ordell, Sven
    Region Östergötland, Public Dental Health Care.
    Self-perceived oral health among 19-year-olds in a Swedish County - A comparative study between 2004 and 20112016In: Swedish Dental Journal, ISSN 0347-9994, Vol. 40, no 1, p. 53-65Article in journal (Refereed)
    Abstract [en]

    For decades, Swedish dental professionals have collected clinical epidemiological data from the dental records. To supplement the epidemiology, Ostergotland County Council decided to examine patient perceptions of oral health: self-rated knowledge, self-perceived oral health, and opinions about oral health. The aim was to compare self-perceived oral health among 19-year-olds to determine differences between genders, various municipalities and between 2004 and 2011. This study analysed the responses from two cross-sectional surveys of the entire population of 19-year-olds in Ostergotland County, Sweden, performed in 2004 and 2011. Of the 2,413 (53 %) (50 % men, 50 % women) 19-year-olds who responded to the questionnaire in 2004 and the 3,803 (67 %) (50 % men, 50 % women) in 2011, most 19-year-olds (88.1 % [2004] and 87.5 % [am]) reported satisfaction with their oral health. Around half of the respondents rated their knowledge on periodontitis as low. Boys rated their knowledge about avoiding periodontitis higher than girls (p&lt;0.05 in 2004 and p&lt;0.001 in 2011). In 2004, 84.7 % reported shooting pain. In 2011 that figure was 83.7 %. The respondents expressed some uncertainty about the benefits of fluoride toothpaste (7.5 % in 2004 and 9.3 % in 2011), especially the boys (10.3 % in 2004 and 10.5 % in 2011). Girls reported both a higher social impact and greater concern about aesthetics related to their oral health. They also reported headache (27.5 %) nearly twice as often as boys (14.2 %) (p&gt;0.001). Responses between the municipalities did not differ, with the exception of items regarding periodontitis. Thus, this study found indications that perceptions of oral health and knowledge in Ostergotland County complied with Swedish Dental Act. The study also found patient perceptions of oral health among 19-year-olds to be good.

  • 336.
    Ahmad, Faiyaz
    et al.
    NHLBI, Translat Med Branch, NIH, Bethesda, MD 20892 USA .
    Lindh, Rebecka
    Lund University, Department Expt Med Science, S-22184 Lund, Sweden .
    Tang, Yan
    NHLBI, Translat Med Branch, NIH, Bethesda, MD 20892 USA .
    Ruishalme, Iida
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Öst, Anita
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Sahachartsiri, Bobby
    NHLBI, Translat Med Branch, NIH, Bethesda, MD 20892 USA .
    Strålfors, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Degerman, Eva
    Lund University, Department Expt Med Science, S-22184 Lund, Sweden .
    C Manganiello, Vincent
    NHLBI, Translat Med Branch, NIH, Bethesda, MD 20892 USA .
    Differential regulation of adipocyte PDE3B in distinct membrane compartments by insulin and the beta(3)-adrenergic receptor agonist CL316243: effects of caveolin-1 knockdown on formation/maintenance of macromolecular signalling complexes2009In: BIOCHEMICAL JOURNAL, ISSN 0264-6021, Vol. 424, no 3, p. 399-410Article in journal (Refereed)
    Abstract [en]

    In adipocytes, PDE3B (phosphodiesterase 3B) is an important regulatory effector in signalling pathways controlled by insulin and cAMP-increasing hormones. Stimulation of 3T3-L1 adipocytes with insulin or the beta(3)-adrenergic receptor agonist CL316243 (termed CL) indicated that insulin preferentially phosphorylated/activated PDE3B associated with internal membranes (endoplasmic reticulum/Golgi), whereas CL preferentially phosphorylated/activated PDE3B associated with caveolae. siRNA (small interfering RNA)-mediated KD (knockdown) of CAV-1 (caveolin-1) in 3T3-L1 adipocytes resulted in down-regulation of expression of membrane-associated PDE3B. Insulin-induced activation of PDE3B was reduced, whereas CL-mediated activation was almost totally abolished. Similar results were obtained in adipocytes from Cav-1-deficient mice. siRNA-mediated KID of CAV-1 in 3T3-L1 adipocytes also resulted in inhibition of CL-stimulated phosphorylation of HSL (hormone-sensitive lipase) and perilipin A, and of lipolysis. Superose 6 gel-filtration chromatography of solubilized membrane proteins from adipocytes stimulated with insulin or CL demonstrated the reversible assembly of distinct macromolecular complexes that contained P-32-phosphorylated PDE3B and signalling molecules thought to be involved in its activation. Insulin- and CL-induced macromolecular complexes were enriched in cholesterol, and contained certain common signalling proteins [14-3-3, PP2A (protein phosphatase 2A) and cav-1]. The complexes present in insulin-stimulated cells contained tyrosine-phosphorylated IRS-1 (insulin receptor substrate 1) and its downstream signalling proteins, whereas CL-activated complexes contained beta(3)-adrenergic receptor, PKA-RII [PKA (cAMP-dependent protein kinase)-regulatory subunit] and HSL. Insulin- and CL-mediated macromolecular complex formation was significantly inhibited by CAV-1 KID. These results suggest that cav-1 acts as a molecular chaperone or scaffolding molecule in cholesterol-rich lipid rafts that may be necessary for the proper stabilization and activation of PDE3B in response to CL and insulin.

  • 337.
    Ahmad, Tariq
    et al.
    Yale Univ, CT USA; Yale Univ, CT USA.
    Lund, Lars H.
    Karolinska Inst, Sweden; Karolinska Univ Hosp, Sweden.
    Rao, Pooja
    Qure Ai, India.
    Ghosh, Rohit
    Qure Ai, India.
    Warier, Prashant
    Qure Ai, India.
    Vaccaro, Benjamin
    Yale Univ, CT USA; Yale Univ, CT USA.
    Dahlström, Ulf
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Cardiology in Linköping.
    OConnor, Christopher M.
    Duke Univ, NC USA.
    Felker, G. Michael
    Duke Univ, NC USA.
    Desai, Nihar R.
    Yale Univ, CT USA; Yale Univ, CT USA.
    Machine Learning Methods Improve Prognostication, Identify Clinically Distinct Phenotypes, and Detect Heterogeneity in Response to Therapy in a Large Cohort of Heart Failure Patients2018In: Journal of the American Heart Association: Cardiovascular and Cerebrovascular Disease, ISSN 2047-9980, E-ISSN 2047-9980, Vol. 7, no 8, article id e008081Article in journal (Refereed)
    Abstract [en]

    Background-Whereas heart failure (HF) is a complex clinical syndrome, conventional approaches to its management have treated it as a singular disease, leading to inadequate patient care and inefficient clinical trials. We hypothesized that applying advanced analytics to a large cohort of HF patients would improve prognostication of outcomes, identify distinct patient phenotypes, and detect heterogeneity in treatment response. Methods and Results-The Swedish Heart Failure Registry is a nationwide registry collecting detailed demographic, clinical, laboratory, and medication data and linked to databases with outcome information. We applied random forest modeling to identify predictors of 1-year survival. Cluster analysis was performed and validated using serial bootstrapping. Association between clusters and survival was assessed with Cox proportional hazards modeling and interaction testing was performed to assess for heterogeneity in response to HF pharmacotherapy across propensity-matched clusters. Our study included 44 886 HF patients enrolled in the Swedish Heart Failure Registry between 2000 and 2012. Random forest modeling demonstrated excellent calibration and discrimination for survival (C-statistic=0.83) whereas left ventricular ejection fraction did not (C-statistic=0.52): there were no meaningful differences per strata of left ventricular ejection fraction (1-year survival: 80%, 81%, 83%, and 84%). Cluster analysis using the 8 highest predictive variables identified 4 clinically relevant subgroups of HF with marked differences in 1-year survival. There were significant interactions between propensity-matched clusters (across age, sex, and left ventricular ejection fraction and the following medications: diuretics, angiotensin-converting enzyme inhibitors, )i-blockers, and nitrates, Pamp;lt;0.001, all). Conclusions-Machine learning algorithms accurately predicted outcomes in a large data set of HF patients. Cluster analysis identified 4 distinct phenotypes that differed significantly in outcomes and in response to therapeutics. Use of these novel analytic approaches has the potential to enhance effectiveness of current therapies and transform future HF clinical trials.

  • 338.
    Ahmadi, Ahmad
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Genetic predisposition and risk factors for neurodegenerative diseases2004Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The inter-individual variability in biotransformation, may lead to differences in activation and detoxification of both endogenous and exogenous compounds. Polymorphism studies in such genes were applied for Parkinson's disease (PD) and Chronic toxic encephalopathy (CTE), two diseases influenced by both genetic and enviromnental factors.

    An elevated median age for the onset of PD was found among GS1M1 gene carriers compared to PD patients being GS1M1 null genotypes (68 years versus 57 years). No similar difference was found for GSTT1. mEPHX (113HH) isoform, which has been suggested as a low activity variant, is over represented in PD patients (OR=3.8, CI 95%, 1.2-11.8).

    Monoamine oxidases (MAO-A and -B) are important in the dopamine metabolism and in the detoxification of neurotoxins and genetic variants in these genes have earlier been assigned to PD. However, no difference was revealed between any of the polymorphisms studied in the MAO-A and -B genes and PD. Smoking displayed an enviromnental exposure with a strong decreased risk for PD in this study (OR=0.40 for men and OR=0.48 for women) but no obvious interaction with the MAO genotypes could be observed.

    Mitochondrial dysfunction and oxidative stress have been hypothesized to contribute to the pathogenesis of PD. The superoxide dismutases (SOD) potentially play an important role in PD by detoxifying superoxide radicals in mitochondria. Polymorphisms neither in superoxide dismutase 2 (SOD2) nor mitochondrial complex I subunit, NDUFV2, were associated with PD.

    An increased risk ratio for CTE was found in smokers with the GSTM1 null genotype (RR=2.5, Cl 95%, 1.4-4.2) or the GSTT1 null genotype (RR=1.4, Ci 95%, 1.02-2.0). In non-smokers GS1M1 null genotype did not confer any risk for CTE. Polymorphisms in mEPHX were not associated with an increased risk for CTE.

    Thus, various genetic and enviromnental factors most likely influence both PD and solvent-induced CTE. Detoxification pathways may represent important protective mechanisms against reactive intermediates, thus genetic predisposition in these pathways could modify the susceptibility and onset of PD and solvent-induced CTE.

    List of papers
    1. GSTM1 and mEPHX polymorphisms in Parkinson's disease and age of onset
    Open this publication in new window or tab >>GSTM1 and mEPHX polymorphisms in Parkinson's disease and age of onset
    Show others...
    2000 (English)In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 269, no 3, p. 676-680Article in journal (Refereed) Published
    Abstract [en]

    Both environmental and genetic factors are involved in the development of PD and biotransformation of exogenous and endogenous compounds and may play a role in inter-individual susceptibility. Therefore, we investigated the presence of null genotypes of GSTM1, GSTT1, and two polymorphisms of mEPHX in subjects with Parkinson's disease and in a reference population. The study included 35 male PD patients and a male control group including 283 subjects. Homozygosity of the histidine (H) 113 isoform of mEPHX was significantly increased in PD patients (odds ratio = 3.8 CI 95% 1.2–11.8) and analysis of allele frequencies displayed an increased frequency of the H-allele among PD patients (odds ratio = 1.9 CI 95% 1.1–3.3). However, a significantly elevated median age for the onset of PD was found among GSTM1 gene carriers (median age = 68 years) compared to PD patients being GSTM1 null genotypes (median age = 57 years). Our observations suggest that (H) 113 isoform of mEPHX, which has been suggested as a low activity isoform, is overrepresented in PD patients and that inherited carriers of the GSTM1 gene postpone the onset of PD. These detoxification pathways may represent important protective mechanisms against reactive intermediates modifying the susceptibility and onset of PD.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-24837 (URN)10.1006/bbrc.2000.2338 (DOI)9235 (Local ID)9235 (Archive number)9235 (OAI)
    Available from: 2009-10-07 Created: 2009-10-07 Last updated: 2017-12-13Bibliographically approved
    2. Monoamine oxidase A and B genes polymorphisms in Parkinson's disease
    Open this publication in new window or tab >>Monoamine oxidase A and B genes polymorphisms in Parkinson's disease
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Parkinson's disease (PD) is a common progressive neurodegenerative disorder characterized by degeneration of nig:rostriatal dopaminergic neurons including the loss of cell bodies in the pars compacta of substantia nigra (SN). The mechanism for neurodegeneration is unknown, but the pathogenesis is considered to be multifactorial involving exposure for toxins, genetic inheritance, age, oxidative stress and mitochondrial electron transport chain defects. This study has been focused on polymorphisms in the genes for the enzymes monoamine oxidase A and B (MAO-A, MAO-B) and relation to smoking for the development of idiopathic Parkinson's disease. MAO enzymes are important in the dopamine metabolism and in the detoxification of neurotoxins. During metabolism of dopamine, MAO generates large amounts of free radicals and hydrogen peroxide, and may damage the neurons in substantia nigra, which has been suggested as a pathologic mechanism for PD.

    Blood samples were collected from 256 PD patients, age 30-80 years, and 582 unrelated control individuals, age 31 - 78 years, from southeastern Sweden.

    Two polymorphisms (exon 8 and exon 14) located in the MAO-A gene and one polymorphism located in the MA O-B gene were examined, with denatming HPLC, PCR-RFLP or DNA sequencing. Genotype and allele frequencies were determined for patients and controls. No statistical significant difference was revealed between any of the polymorphisms in the MAO-A and MAO-B genes and Parkinson's disease. Smoking displayed an enviromnental exposure with a strong decreased risk for both male (OR=0.40, 95% CI 0.25 - 0.63) and female (OR=0.48, 95% CI 0.25-0.89) PD without any interaction with MAO genotype.

    The polymorphisms in MAO genes might therefore not be acting as modifiers of risk for developing of PD either by itself or by interacting with smoking. With respect to the size of the study (256 PD patients and 582 controls) MAO polymorphisms do not represent any predisposing factor or a weak PD susceptibility factor.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-84799 (URN)
    Available from: 2012-10-22 Created: 2012-10-22 Last updated: 2012-10-22Bibliographically approved
    3. Manganese superoxide dismutase and NDUFV2 polymorphisms and susceptibility to Parkinson's disease
    Open this publication in new window or tab >>Manganese superoxide dismutase and NDUFV2 polymorphisms and susceptibility to Parkinson's disease
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Mitochondrial dysfunction has been hypothesized to contribute to the pathogenesis of Parkinson's disease (PD). Oxidative stress and production of oxygen radicals is produced in mitochondria. The superoxide dismutases (SOD) potentially play an important role in PD by detoxifying superoxide radicals. Oxidative stress has also an important role to decrease Complex I activity in the mitochondria. In addition, Complex I contains several subunits, where one, NDUFV2, plays a major role in the electron transport pathway of Complex I in substantia nigra.

    The aim of this project was to study polymorphisms in MTS-SOD2 and the Complex I subunit, NDUFV2 as predisposing factors for the development of idiopathic PD.

    Blood samples from 200 PD and 404 population controls were collected from the Southeastern part of Sweden. DNA was isolated and the polymorphisms were analyzed by pyrosequencing and direct dideoxy termination sequencing.

    Genotypes and allele frequencies were compared for the patient and control groups with Χ2 statistics. No statistical significant difference was evident for any of the polymorphisms neither in MTS-SOD2 (OR=0<85, 95% CI, 0<52-1.38) nor NDUFV2 (OR=0.64, 95% CI, 0.24-1.64) genes and PD.

    These results indicate that the MTS-SOD2 and NDUFV2 gene variants do not contribute to PD pathogenesis.

    Keywords
    SOD2, NDUFV2, polymorphisms, Parkinson's disease
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-84800 (URN)
    Available from: 2012-10-22 Created: 2012-10-22 Last updated: 2012-10-22Bibliographically approved
    4. Glutathione S-transferase M1 null genotype as a risk modifier for solvent-induced chronic toxic encephalopathy
    Open this publication in new window or tab >>Glutathione S-transferase M1 null genotype as a risk modifier for solvent-induced chronic toxic encephalopathy
    Show others...
    1996 (English)In: Scandinavian Journal of Work, Environment and Health, ISSN 0355-3140, E-ISSN 1795-990X, Vol. 22, no 5, p. 360-363Article in journal (Refereed) Published
    Abstract [en]

    Objectives Exposure to organic solvents increases the risk of neuropsychiatric disability or chronic toxic encephalopathy (CTE). Polymorphisms in the biotransformation of xenobiotics and solvents may influence individual susceptibility to develop toxic effects. In this study the problem of whether there could be any association between the glutathione S-transferase M1 (GSTM1) null genotype and the risk for CTE, with regard to solvent exposure, was investigated.

    Methods Sixty patients referred to a clinic because of some degree of some degrees of psychiatric or neurological symptoms, as well as exposure to solvents, were examined by means of a validated questionnaire and psychometric testing. The degree of exposure to solvents was assessed by a thorough interview. According to clinical findings, the patients were classified into three categories as those with solvent-induced CTE, those with incipient CTE, and those who were non-CTE patients. Afterwards, leukocyte DNA (deoxyribonucleic acid) was isolated and the GSTM1 null genotype was determined by an assay based on polymerase chain reaction, blindly with regard to both exposure and disease status.

    Results The relative proportion (RP) of GSTM1 null genotypes was significantly increased for patients with a diagnosed CTE when they were compared with non-CTE patients (RP 2.55, 95% confidence interval 1.0--6.2). Dichotomizing the patients by high and low exposure revealed an increased risk for both GSTM1 gene carriers and the GSTM1 null genotype in the high-exposure group, the relative risks (RR) being 4.5 and 7.9, respectively. The chi-square for the Mantel extension for trend was 6.2 (P=0.025).

    Conclusion The GSTM1 null genotype acts as a risk modifier for CTE among patients occupationally exposed to solvents. The risk seems to increase in a dose-dependent fashion.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-84801 (URN)10.5271/sjweh.154 (DOI)
    Available from: 2012-10-22 Created: 2012-10-22 Last updated: 2017-12-07Bibliographically approved
    5. Interaction between smoking and glutathione S-transferase polymorphisms in solvent-induced chronic toxic encephalopathy
    Open this publication in new window or tab >>Interaction between smoking and glutathione S-transferase polymorphisms in solvent-induced chronic toxic encephalopathy
    2002 (English)In: Toxicology and industrial health, ISSN 0748-2337, E-ISSN 1477-0393, Vol. 18, no 6, p. 289-296Article in journal (Refereed) Published
    Abstract [en]

    Exposure to organic solvents is still common in industrial and other work environments, and increases the risk of chronic toxic encephalopathy (CTE). Genetic variation in metabolic enzymes for solvents and other xenobiotics may modify the risk of developing toxic effects. Therefore, we investigated the presence of null genotypes for glutathione S-transferases M1 and T1 (GSTM1, GSTT1) and two genetic polymorphisms of microsomal epoxide hydrolase (mEPHX) in relation to the risk for chronic toxic encephalopathy (CTE) when exposed to solvents and smoking. We genotyped 115 patients who were classified into three categories: CTE (n = 56), incipient CTE (n = 27) and non-CTE (n = 32) patients. DNA was isolated from leucocytes and the GSTM 1 and GSTT1 null genotypes were determined by multiplex-polymerase chain reaction. The two polymorphisms of mEPHX were analysed by PCR-RFLP (restriction fragment length polymorphism) based assays. All analyses were performed blindly with regard to both exposure and disease status. An increased binomial regression risk ratio = 2.5, 95% confidence interval (CI) 1.5-4.2, of the GSTM1 null genotype for CTE was found in smokers and for the GSTT1 null genotype (binomial regression risk ratio 1.5, 95% CI 1.0-2.0). In nonsmokers, the GSTM1 null genotype did not confer any risk for CTE. None of the studied mEPHX polymorphisms were associated with an increased risk for CTE. We suggest that the GSTM1 null genotype in smokers is a possible risk for solvent-induced CTE.

    Keywords
    chronic toxic encephalopathy, molecular epidemiology, polymorphism, smoking, solvent exposure
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-46280 (URN)10.1191/0748233702th152oa (DOI)
    Available from: 2009-10-11 Created: 2009-10-11 Last updated: 2017-12-13Bibliographically approved
  • 339.
    Ahmadi, Ahmad
    et al.
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Bivik, Cecilia
    Linköping University, Department of Biomedicine and Surgery, Dermatology. Linköping University, Faculty of Health Sciences.
    Söderkvist, Peter
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Monoamine oxidase A and B genes polymorphisms in Parkinson's diseaseManuscript (preprint) (Other academic)
    Abstract [en]

    Parkinson's disease (PD) is a common progressive neurodegenerative disorder characterized by degeneration of nig:rostriatal dopaminergic neurons including the loss of cell bodies in the pars compacta of substantia nigra (SN). The mechanism for neurodegeneration is unknown, but the pathogenesis is considered to be multifactorial involving exposure for toxins, genetic inheritance, age, oxidative stress and mitochondrial electron transport chain defects. This study has been focused on polymorphisms in the genes for the enzymes monoamine oxidase A and B (MAO-A, MAO-B) and relation to smoking for the development of idiopathic Parkinson's disease. MAO enzymes are important in the dopamine metabolism and in the detoxification of neurotoxins. During metabolism of dopamine, MAO generates large amounts of free radicals and hydrogen peroxide, and may damage the neurons in substantia nigra, which has been suggested as a pathologic mechanism for PD.

    Blood samples were collected from 256 PD patients, age 30-80 years, and 582 unrelated control individuals, age 31 - 78 years, from southeastern Sweden.

    Two polymorphisms (exon 8 and exon 14) located in the MAO-A gene and one polymorphism located in the MA O-B gene were examined, with denatming HPLC, PCR-RFLP or DNA sequencing. Genotype and allele frequencies were determined for patients and controls. No statistical significant difference was revealed between any of the polymorphisms in the MAO-A and MAO-B genes and Parkinson's disease. Smoking displayed an enviromnental exposure with a strong decreased risk for both male (OR=0.40, 95% CI 0.25 - 0.63) and female (OR=0.48, 95% CI 0.25-0.89) PD without any interaction with MAO genotype.

    The polymorphisms in MAO genes might therefore not be acting as modifiers of risk for developing of PD either by itself or by interacting with smoking. With respect to the size of the study (256 PD patients and 582 controls) MAO polymorphisms do not represent any predisposing factor or a weak PD susceptibility factor.

  • 340.
    Ahmadi, Ahmad
    et al.
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Fredriksson, Mats
    Linköping University, Department of Molecular and Clinical Medicine, Occupational and Environmental Medicine. Linköping University, Faculty of Health Sciences.
    Jerregård, H.
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Åkerbäck, Anita
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Fall, Per-Arne
    Linköping University, Department of Neuroscience and Locomotion, Geriatrics. Linköping University, Faculty of Health Sciences.
    Rannug, A.
    National Institute for Working Life, Solna and Inst. of Environ. Medicine, Karolinska Institutet, Stockholm, Sweden.
    Axelson, Olav
    Linköping University, Department of Molecular and Clinical Medicine, Occupational and Environmental Medicine. Linköping University, Faculty of Health Sciences.
    Söderkvist, Peter
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    GSTM1 and mEPHX polymorphisms in Parkinson's disease and age of onset2000In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 269, no 3, p. 676-680Article in journal (Refereed)
    Abstract [en]

    Both environmental and genetic factors are involved in the development of PD and biotransformation of exogenous and endogenous compounds and may play a role in inter-individual susceptibility. Therefore, we investigated the presence of null genotypes of GSTM1, GSTT1, and two polymorphisms of mEPHX in subjects with Parkinson's disease and in a reference population. The study included 35 male PD patients and a male control group including 283 subjects. Homozygosity of the histidine (H) 113 isoform of mEPHX was significantly increased in PD patients (odds ratio = 3.8 CI 95% 1.2–11.8) and analysis of allele frequencies displayed an increased frequency of the H-allele among PD patients (odds ratio = 1.9 CI 95% 1.1–3.3). However, a significantly elevated median age for the onset of PD was found among GSTM1 gene carriers (median age = 68 years) compared to PD patients being GSTM1 null genotypes (median age = 57 years). Our observations suggest that (H) 113 isoform of mEPHX, which has been suggested as a low activity isoform, is overrepresented in PD patients and that inherited carriers of the GSTM1 gene postpone the onset of PD. These detoxification pathways may represent important protective mechanisms against reactive intermediates modifying the susceptibility and onset of PD.

  • 341.
    Ahmadi, Ahmad
    et al.
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Johansson, Sofia
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Söderkvist, Peter
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Manganese superoxide dismutase and NDUFV2 polymorphisms and susceptibility to Parkinson's diseaseManuscript (preprint) (Other academic)
    Abstract [en]

    Mitochondrial dysfunction has been hypothesized to contribute to the pathogenesis of Parkinson's disease (PD). Oxidative stress and production of oxygen radicals is produced in mitochondria. The superoxide dismutases (SOD) potentially play an important role in PD by detoxifying superoxide radicals. Oxidative stress has also an important role to decrease Complex I activity in the mitochondria. In addition, Complex I contains several subunits, where one, NDUFV2, plays a major role in the electron transport pathway of Complex I in substantia nigra.

    The aim of this project was to study polymorphisms in MTS-SOD2 and the Complex I subunit, NDUFV2 as predisposing factors for the development of idiopathic PD.

    Blood samples from 200 PD and 404 population controls were collected from the Southeastern part of Sweden. DNA was isolated and the polymorphisms were analyzed by pyrosequencing and direct dideoxy termination sequencing.

    Genotypes and allele frequencies were compared for the patient and control groups with Χ2 statistics. No statistical significant difference was evident for any of the polymorphisms neither in MTS-SOD2 (OR=0<85, 95% CI, 0<52-1.38) nor NDUFV2 (OR=0.64, 95% CI, 0.24-1.64) genes and PD.

    These results indicate that the MTS-SOD2 and NDUFV2 gene variants do not contribute to PD pathogenesis.

  • 342.
    Ahmadi, Ahmad
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Jonsson, Pia
    Linköping University, Department of Molecular and Clinical Medicine, Occupational and Environmental Medicine. Linköping University, Faculty of Health Sciences.
    Flodin, Ulf
    Linköping University, Department of Clinical and Experimental Medicine, Occupational and Environmental Medicine. Linköping University, Faculty of Health Sciences.
    Söderkvist, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Interaction between smoking and glutathione S-transferase polymorphisms in solvent-induced chronic toxic encephalopathy2002In: Toxicology and industrial health, ISSN 0748-2337, E-ISSN 1477-0393, Vol. 18, no 6, p. 289-296Article in journal (Refereed)
    Abstract [en]

    Exposure to organic solvents is still common in industrial and other work environments, and increases the risk of chronic toxic encephalopathy (CTE). Genetic variation in metabolic enzymes for solvents and other xenobiotics may modify the risk of developing toxic effects. Therefore, we investigated the presence of null genotypes for glutathione S-transferases M1 and T1 (GSTM1, GSTT1) and two genetic polymorphisms of microsomal epoxide hydrolase (mEPHX) in relation to the risk for chronic toxic encephalopathy (CTE) when exposed to solvents and smoking. We genotyped 115 patients who were classified into three categories: CTE (n = 56), incipient CTE (n = 27) and non-CTE (n = 32) patients. DNA was isolated from leucocytes and the GSTM 1 and GSTT1 null genotypes were determined by multiplex-polymerase chain reaction. The two polymorphisms of mEPHX were analysed by PCR-RFLP (restriction fragment length polymorphism) based assays. All analyses were performed blindly with regard to both exposure and disease status. An increased binomial regression risk ratio = 2.5, 95% confidence interval (CI) 1.5-4.2, of the GSTM1 null genotype for CTE was found in smokers and for the GSTT1 null genotype (binomial regression risk ratio 1.5, 95% CI 1.0-2.0). In nonsmokers, the GSTM1 null genotype did not confer any risk for CTE. None of the studied mEPHX polymorphisms were associated with an increased risk for CTE. We suggest that the GSTM1 null genotype in smokers is a possible risk for solvent-induced CTE.

  • 343.
    Ahmed, Ali
    Linköping University, Department of Management and Engineering, Economics. Linköping University, Faculty of Arts and Sciences.
    Co-ethnic preferences in a cooking game: a study based on Come Dine With Me in Sweden2013In: Ethnic and Racial Studies, ISSN 0141-9870, E-ISSN 1466-4356, Vol. 36, no 12, p. 2220-2236Article in journal (Refereed)
    Abstract [en]

    This study examines ethnic preferences using data from the television cooking show Come Dine With Me in Sweden. Amateur chefs compete by hosting dinner parties. Contestants rate each others performance and the host with the highest ratings wins a cash prize. The show gives an unorthodox opportunity to study ethnic preferences in a high-stakes game environment. The analysis of the collected data shows that native Swedish contestants rate co-ethnic hosts significantly more favourably than they rate other hosts, demonstrating the existence of co-ethnic preferences. This observation seems to be an outcome of own-group favouritism rather than dislike against other groups. Also, the observed co-ethnic preference is assumed to be subtle or non-conscious based on the nature of the analysed data.

  • 344.
    Ahmed, Tamer A. E.
    et al.
    University of Ottawa, Ontario, Canada.
    Giulivi, Antonio
    The Ottawa Hospital, Ontario, Canada.
    Griffith, May
    University of Ottawa, Ontario, Canada.
    Hincke, Max
    University of Ottawa, Ontario, Canada.
    Fibrin Glues in Combination with Mesenchymal Stem Cells to Develop a Tissue-Engineered Cartilage Substitute2011In: Tissue Engineering. Parts A, B and C, ISSN 2152-4947, E-ISSN 2152-4955, Vol. 17, no 3-4, p. 323-335Article in journal (Refereed)
    Abstract [en]

     Damage of cartilage due to traumatic or pathological conditions results in disability and severe pain. Regenerative medicine, using tissue engineering-based constructs to enhance cartilage repair by mobilizing chondrogenic cells, is a promising approach for restoration of structure and function. Fresh fibrin (FG) and platelet-rich fibrin (PR-FG) glues produced by the CryoSeal (R) FS System, in combination with human bone marrow-derived mesenchymal stem cells (BM-hMSCs), were evaluated in this study. We additionally tested the incorporation of heparin-based delivery system (HBDS) into these scaffolds to immobilize endogenous growth factors as well as exogenous transforming growth factor-beta(2). Strongly, CD90+ and CD105+ hMSCs were encapsulated into FG and PR-FG with and without HBDS. Encapsulation of hMSCs in PR-FG led to increased expression of collagen II gene at 2.5 weeks; however, no difference was observed between FG and PR-FG at 5 weeks. The incorporation of HBDS prevented the enhancement of collagen II gene expression. BM-hMSCs in FG initially displayed enhanced aggrecan gene expression and increased accumulation of Alcian blue-positive extracellular matrix; incorporation of HBDS into these glues did not improve aggrecan gene expression and extracellular matrix accumulation. The most significant effect on cartilage marker gene expression and accumulation was observed after encapsulation of hMSCs in FG. We conclude that FG is more promising than PR-FG as a scaffold for chondrogenic differentiation of hMSCs; however, immobilization of growth factors inside these fibrin scaffolds with the HBDS system has a negative impact on this process. In addition, BM-hMSCs are valid and potentially superior alternatives to chondrocytes for tissue engineering of articular cartilage.

  • 345.
    Ahn, Henrik
    et al.
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Baranowski, Jacek
    Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Dahlin, Lars-Göran
    Linköping University, Department of Medical and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Thoracic and Vascular Surgery in Östergötland.
    Nielsen, Niels-Erik
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Cardiology UHL.
    Nylander, Eva
    Linköping University, Center for Medical Image Science and Visualization, CMIV. Linköping University, Department of Medical and Health Sciences, Clinical Physiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    Wallby, Lars
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Clinical Physiology UHL.
    TAVI without concomitant balloon dilatation2012Conference paper (Other academic)
  • 346.
    Ahn, Henrik
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Baranowski, Jacek
    Myasnikova, Irina
    Rahgozar, Mohammad
    Linköping University, Department of Clinical and Experimental Medicine.
    Delshad, Baz
    First in man: wireless pressure sensors in left heart rooms'2014Conference paper (Refereed)
  • 347.
    Ahn, Henrik Casimir
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Mitral valve surgery - current results and future development to catheter based approaches2006In: International Society of Extracorporeal Circulation - Cardiac Surgery beyond 2006,2006, 2006Conference paper (Other academic)
  • 348.
    Ahn, Henrik Casimir
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Medicine and Care, Thoracic Surgery. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    The Impella temporary assist device, the Swedish experience2006In: International Society of Extracorporeal Circulation - Cardiac Surgery beyond 2006,2006, 2006Conference paper (Other academic)
  • 349.
    Ahn, Henrik Casimir
    et al.
    Linköping University, Department of Medicine and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Baranowski, J
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Nielsen, Nils Erik
    Linköping University, Department of Medicine and Health Sciences, Cardiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Nylander, Eva
    Linköping University, Department of Medicine and Health Sciences, Clinical Physiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Tamas, Eva
    Linköping University, Department of Medicine and Health Sciences, Thoracic Surgery. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Thoracic and Vascular Surgery.
    Wallby, Lars
    Linköping University, Department of Medicine and Health Sciences, Cardiology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Clinical Physiology.
    Transcatheter aortic valve implantation in high-risk surgical candidates with low risk-scores1984Conference paper (Other academic)
  • 350.
    Ahn, Henrik Casimir
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Baranowski, Jacek
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Clinical Physiology in Linköping.
    Dahlin, Lars-Göran
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Thoracic and Vascular Surgery.
    Nielsen, Niels Erik
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Cardiology in Linköping.
    Transvenous Implantation of a Stent Valve in Patients With Degenerated Mitral Prostheses and Native Mitral Stenosis2016In: Annals of Thoracic Surgery, ISSN 0003-4975, E-ISSN 1552-6259, Vol. 101, no 6, p. 2279-2284Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: The purpose of this study was to report the use of a transvenous transseptal approach using a stent valve in patients with degenerated biological mitral valve prostheses, regurgitation after mitral repair, and native mitral stenosis.

    METHODS: Ten patients (median age, 74 years; range, 20-89 years; 5 men and 5 women) with degenerated mitral bioprosthetic valves (n = 7), failed mitral repair (n = 1), or calcified native stenotic valves (n = 2) underwent transvenous implantation of a stent valve.

    RESULTS: The procedure was initially successful in all patients. Predilation was performed for balloon sizing only in the 2 patients with native mitral stenosis. The stent valve was deployed during 1 period of rapid pacing. A guidewire, as a loop from the right femoral vein and through the left ventricular apex, facilitated a good angle and secure positioning of the stent valve. An ultrasonographically guided puncture of the apex was carried out in 6 patients, and in the other 4 we performed a minithoracotomy before apical puncture. All valves were implanted in a good position with improved function and without significant paravalvular leakage (PVL). There were no periprocedural deaths. The 30-day survival was 80% (8 of 10 patients), and 60% (6 of 10) of patients were still alive a median time of 290 days after the procedure.

    CONCLUSIONS: Transvenous transseptal implantation of a stent valve was performed in 10 patients with mitral valve disease, with good early functional results. These high-risk patients must be carefully selected by a multidisciplinary team because the procedure carries a high mortality.

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