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        <titl xml:lang="sv">Upprepade lumbalpunktioner inom 3 dagar kan påverka biomarkörer i likvor - Upprepade lumbalpunktioner. Efter sömndeprivering och 3 dagar senare, efter återhämtningssömn</titl>
        <parTitl xml:lang="en">Repeated lumbar punctures within 3 days may affect CSF biomarker levels - Repeated lumbar punctures. After sleep deprivation and 3 days later, after recovery sleep</parTitl>
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        <titl xml:lang="sv">Upprepade lumbalpunktioner inom 3 dagar kan påverka biomarkörer i likvor - Upprepade lumbalpunktioner. Efter sömndeprivering och 3 dagar senare, efter återhämtningssömn</titl>
        <parTitl xml:lang="en">Repeated lumbar punctures within 3 days may affect CSF biomarker levels - Repeated lumbar punctures. After sleep deprivation and 3 days later, after recovery sleep</parTitl>
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        <IDNo agency="DOI">10.1093/sleep/zsy025</IDNo>
        <IDNo agency="DOI">10.1186/s12987-019-0157-2</IDNo>
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        <AuthEnty xml:lang="en" affiliation="University of Gothenburg">Olsson, Martin</AuthEnty>
        <AuthEnty xml:lang="sv" affiliation="Göteborgs universitet">Olsson, Martin</AuthEnty>
        <AuthEnty xml:lang="en" affiliation="University of Gothenburg">Ärlig, Johan</AuthEnty>
        <AuthEnty xml:lang="sv" affiliation="Göteborgs universitet">Ärlig, Johan</AuthEnty>
        <AuthEnty xml:lang="en" affiliation="the Institute of Medicine, University of Gothenburg">Hedner, Jan</AuthEnty>
        <AuthEnty xml:lang="sv" affiliation="Institutionen för medicin, Göteborgs universitet">Hedner, Jan</AuthEnty>
        <AuthEnty xml:lang="en" affiliation="Institute of Neuroscience and Physiology, University of Gothenburg">Blennow, Kaj</AuthEnty>
        <AuthEnty xml:lang="sv" affiliation="Institutionen för neurovetenskap och fysiologi, Göteborgs universitet">Blennow, Kaj</AuthEnty>
        <AuthEnty xml:lang="en" affiliation="Institute of Neuroscience and Physiology, University of Gothenburg">Zetterberg, Henrik</AuthEnty>
        <AuthEnty xml:lang="sv" affiliation="Institutionen för neurovetenskap och fysiologi, Göteborgs universitet">Zetterberg, Henrik</AuthEnty>
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        <distDate xml:lang="en" date="2019-11-29" />
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    <stdyInfo>
      <subject>
        <keyword xml:lang="en" vocab="MeSH" vocabURI="http://id.nlm.nih.gov/mesh/D002555">Cerebrospinal Fluid</keyword>
        <keyword xml:lang="sv" vocab="MeSH" vocabURI="http://id.nlm.nih.gov/mesh/D002555">Cerebrospinalvätska</keyword>
        <keyword xml:lang="en" vocab="MeSH" vocabURI="http://id.nlm.nih.gov/mesh/D002556">Cerebrospinal Fluid Proteins</keyword>
        <keyword xml:lang="sv" vocab="MeSH" vocabURI="http://id.nlm.nih.gov/mesh/D002556">Likvorproteiner</keyword>
        <keyword xml:lang="en" vocab="MeSH" vocabURI="http://id.nlm.nih.gov/mesh/D016229">Amyloid beta-Peptides</keyword>
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      </subject>
      <abstract xml:lang="en" contentType="abstract">As an extension of a study on the relationship between sleep deprivation and cerebrospinal fluid (CSF) biomarkers for Alzheimer’s disease, we performed two Lumbar punctures (LPs) within three days in 13 healthy volunteers. Our aim was to investigate CSF biomarker dynamics in relation to sleep deprivation.  An unexpected sharp rise in biomarker concentrations in the second sample made us consider an artifact and we therefore repeated the experiment, but without sleep restriction, in four additional individuals. A similar rise in biomarker levels were evident, suggesting an inherent methodological problem with repeated LPs.

Biomarker concentrations from each individual lumbar puncture. First puncture immediately after sleep deprivation. Second puncture three days later, after recovery sleep.</abstract>
      <abstract xml:lang="sv" contentType="abstract">En förlängning av en studie om förhållandet mellan sömnbrist och biomarkörer för Alzheimers sjukdom, i cerebrospinalvätska (CSF). Friska frivilliga (N=13) utsattes för upprepade lumbalpunktioner med tre dagars mellanrum. Vårt mål var att undersöka CSF-dynamik i förhållande till sömnbrist. En oväntad kraftig ökning av biomarkörkoncentrationerna i det andra provet fick oss att misstänka en artefakt och vi upprepade därför experimentet, men utan sömnbegränsning, i fyra ytterligare individer. Vi kunde då se en liknande ökning i biomarkörnivåer, vilket antyder ett inneboende metodproblem med upprepade lumbalpunktioner.

Biomarkörkoncentrationer från varje lumbalpunktion. Första punktion direkt efter sömndeprivering. Andra punktion tre dagar senare, efter återhämtningssömn.</abstract>
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        <universe xml:lang="en">Healthy volunteers</universe>
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        <sampProc xml:lang="en">13 healthy volunteers recruited by posters on university campus. 20-40 years of age with no sleep disturbances. Body-Mass-index (BMI) &lt; 30 kg/m2. No continual use of medication or relevant chronic diseases. Self-reported normal bedtime &lt; 00.00, regular morning awakening hours 06.00-09.00, habitual sleep duration of between 6.5-8.5 hours and absence of sleep disturbances (such as chronic insomnia/daytime sleepiness/narcolepsy). Epworth Sleepiness Scale (ESS) score &lt; 11.<concept vocab="DDI Sampling Procedure" vocabURI="https://vocabularies.cessda.eu/v2/vocabularies/SamplingProcedure/2.0.1?languageVersion=en-2.0.1">13 healthy volunteers recruited by posters on university campus. 20-40 years of age with no sleep disturbances. Body-Mass-index (BMI) &lt; 30 kg/m2. No continual use of medication or relevant chronic diseases. Self-reported normal bedtime &lt; 00.00, regular morning awakening hours 06.00-09.00, habitual sleep duration of between 6.5-8.5 hours and absence of sleep disturbances (such as chronic insomnia/daytime sleepiness/narcolepsy). Epworth Sleepiness Scale (ESS) score &lt; 11.</concept></sampProc>
        <sampProc xml:lang="sv">13 friska frivilliga rekryterade genom affischer på universitetsområde. 20-40 år utan sömnstörningar. Body-Mass-index (BMI) &lt;30 kg / m2. Ingen kontinuerlig användning av mediciner och inga kroniska sjukdomar. Självrapporterad normal sänggång &lt;00.00, uppstigning 06.00-09.00, sömnduration 6,5-8,5 timmar och frånvaro av sömnstörningar (såsom kronisk sömnlöshet / sömnighet på dagtid / narkolepsi). Epworth Sleepiness Scale (ESS) poäng &lt;11.<concept vocab="DDI Sampling Procedure" vocabURI="https://vocabularies.cessda.eu/v2/vocabularies/SamplingProcedure/2.0.1?languageVersion=sv-2.0.1">13 friska frivilliga rekryterade genom affischer på universitetsområde. 20-40 år utan sömnstörningar. Body-Mass-index (BMI) &lt;30 kg / m2. Ingen kontinuerlig användning av mediciner och inga kroniska sjukdomar. Självrapporterad normal sänggång &lt;00.00, uppstigning 06.00-09.00, sömnduration 6,5-8,5 timmar och frånvaro av sömnstörningar (såsom kronisk sömnlöshet / sömnighet på dagtid / narkolepsi). Epworth Sleepiness Scale (ESS) poäng &lt;11.</concept></sampProc>
        <sampProc xml:lang="en">Other<concept vocab="DDI Sampling Procedure" vocabURI="https://vocabularies.cessda.eu/v2/vocabularies/SamplingProcedure/2.0.1?languageVersion=en-2.0.1">Other</concept></sampProc>
        <sampProc xml:lang="sv">Övrigt<concept vocab="DDI Sampling Procedure" vocabURI="https://vocabularies.cessda.eu/v2/vocabularies/SamplingProcedure/2.0.1?languageVersion=sv-2.0.1">Övrigt</concept></sampProc>
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        <restrctn xml:lang="en">Access to data through SND. Data are freely accessible.</restrctn>
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            <titl xml:lang="sv">Olsson M, Arlig J, Hedner J, Blennow K, Zetterberg H. Sleep deprivation and cerebrospinal fluid biomarkers for Alzheimer's disease. Sleep. 2018;41(5). https://doi.org/10.1093/sleep/zsy025</titl>
            <parTitl xml:lang="en">Olsson M, Arlig J, Hedner J, Blennow K, Zetterberg H. Sleep deprivation and cerebrospinal fluid biomarkers for Alzheimer's disease. Sleep. 2018;41(5). https://doi.org/10.1093/sleep/zsy025</parTitl>
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            <titl xml:lang="sv">Olsson, M., Ärlig, J., Hedner, J. et al. Repeated lumbar punctures within 3 days may affect CSF biomarker levels. Fluids Barriers CNS 16, 37 (2019) doi:10.1186/s12987-019-0157-2</titl>
            <parTitl xml:lang="en">Olsson, M., Ärlig, J., Hedner, J. et al. Repeated lumbar punctures within 3 days may affect CSF biomarker levels. Fluids Barriers CNS 16, 37 (2019) doi:10.1186/s12987-019-0157-2</parTitl>
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