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        <r:String xml:lang="sv">Data över hur upprepade lumbalpunktioner inom 3 dagar kan påverka biomarkörer i likvor</r:String>
        <r:String xml:lang="en">Data showing how Repeated Lumbar Punctures within 3 days may affect CSF Biomarker Levels</r:String>
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          <r:String xml:lang="en">University of Gothenburg</r:String>
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          <r:String xml:lang="sv">Göteborgs universitet</r:String>
          <r:String xml:lang="en">University of Gothenburg</r:String>
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        <r:SimpleDate>2024-08-08</r:SimpleDate>
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      <r:Content xml:lang="sv">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 (N=4). Vi kunde då se en liknande ökning i biomarkörnivåer, vilket antyder ett inneboende metodproblem med upprepade lumbalpunktioner.

Experiment 1: Upprepade lumbalpunktioner inom 3 dagar utan sömnintervention.
Försökspersoner som med kontrollerad normalsömn. Lumbalpunktion med 3 dagars mellanrum. Biomarkörkoncentrationer från varje enskild lumbalpunktion.

Experiment 2: Efter sömndeprivering och 3 dagar senare, efter återhämtningssömn.
Biomarkörkoncentrationer från varje lumbalpunktion. Första punktion direkt efter sömndeprivering. Andra punktion tre dagar senare, efter återhämtningssömn.</r:Content>
      <r:Content xml:lang="en">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 (N=13). 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 (N=4). A similar rise in biomarker levels were evident, suggesting an inherent methodological problem with repeated LPs.

Experiment 1: Repeated lumbar punctures within 3 days without sleep intervention.
Participants with controled normal sleep. Biomarker concentrations from each individual lumbar puncture.

Experiment 2: After sleep deprivation and 3 days later, after recovery sleep.
Biomarker concentrations from each individual lumbar puncture. First puncture immediately after sleep deprivation. Second puncture three days later, after recovery sleep.</r:Content>
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        <r:Keyword xml:lang="en" controlledVocabularyID="D002555" controlledVocabularyName="MeSH">Cerebrospinal Fluid</r:Keyword>
        <r:Keyword xml:lang="sv" controlledVocabularyID="D002555" controlledVocabularyName="MeSH">Cerebrospinalvätska</r:Keyword>
        <r:Keyword xml:lang="en" controlledVocabularyID="D002556" controlledVocabularyName="MeSH">Cerebrospinal Fluid Proteins</r:Keyword>
        <r:Keyword xml:lang="sv" controlledVocabularyID="D002556" controlledVocabularyName="MeSH">Likvorproteiner</r:Keyword>
        <r:Keyword xml:lang="en" controlledVocabularyID="D016229" controlledVocabularyName="MeSH">Amyloid beta-Peptides</r:Keyword>
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